kwws˛ zzz sofv qhw - uppaginas.fe.up.pt/~asousa/sind/acetat/plc_tutor__plcsnet.pdf · 56 &rpp...

62
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB 3/&78725 KWWSZZZSOFVQHW E\3KLO0HORUH

Upload: trandung

Post on 28-Apr-2019

218 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

3/&�78725

KWWS���ZZZ�SOFV�QHW�

E\�3KLO�0HORUH

Page 2: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH � ���� 3/& 78725

Page 3: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH �

7DEOH�2I�&RQWHQWVKWWS���ZZZ�SOFV�QHW�FRQWHQWV�VKWPO

6WDUWHUV

:KDW�LV�D�3/&"

3/&�+LVWRU\

7KHRU\�RI�2SHUDWLRQ

7KH�,QWHUQDOV

+RZ�LW�:RUNV

5HVSRQVH�7LPH

(IIHFWV�RI�5HVSRQVH�7LPH

&UHDWLQJ�3URJUDPV

5HOD\V

5HSODFLQJ�5HOD\V

%DVLF�,QVWUXFWLRQV

%DVLF�3URJUDP�([DPSOH

3/&�5HJLVWHUV

$�/HYHO�$SSOLFDWLRQ

+RZ�D�/DGGHU�LV�6FDQQHG

0DLQ�,QVWUXFWLRQ�6HW

/DWFKLQJ�,QVWUXFWLRQV

&RXQWHUV

7LPHUV

7LPHU�$FFXUDF\

2QH�6KRWV

0DVWHU�&RQWUROV

6KLIW�5HJLVWHUV

0RYLQJ�'DWD

1XPEHUV

0DWK

1XPEHU�6\VWHPV

%RROHDQ�0DWK

Page 4: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH � ���� 3/& 78725

:LULQJ

'&�,QSXWV

$&�,QSXWV

5HOD\�2XWSXWV

7UDQVLVWRU�2XWSXWV

&RPPXQLFDWLRQV

&RPPXQLFDWLRQV�+LVWRU\

56�����&RPP��KDUGZDUH�

56�����&RPP��VRIWZDUH�

8VLQJ�56������/DGGHU�'LDJUDP�

Page 5: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH �

:KDW�LV�D�3/&"KWWS���ZZZ�SOFV�QHW�ZKDWLV��KWP

$�3/&��L�H��3URJUDPPDEOH�/RJLF�&RQWUROOHU��LV�D�GHYLFH�WKDW�ZDV�LQYHQWHG�WR�UHSODFH

WKH�QHFHVVDU\�VHTXHQWLDO�UHOD\�FLUFXLWV�IRU�PDFKLQH�FRQWURO��7KH�3/&�ZRUNV�E\�ORRNLQJ

DW�LWV�LQSXWV�DQG�GHSHQGLQJ�XSRQ�WKHLU�VWDWH��WXUQLQJ�RQ�RII�LWV�RXWSXWV��7KH�XVHU�HQWHUV

D�SURJUDP��XVXDOO\�YLD�VRIWZDUH��WKDW�JLYHV�WKH�GHVLUHG�UHVXOWV�

)RU�H[DPSOH��OHWV�DVVXPH�WKDW�ZKHQ�D�VZLWFK�WXUQV�RQ�ZH�ZDQW�WR�WXUQ�D�VROHQRLG�RQ

IRU���VHFRQGV�DQG�WKHQ�WXUQ�LW�RII�UHJDUGOHVV�RI�KRZ�ORQJ�WKH�VZLWFK�LV�RQ�IRU��:H�FDQ

GR�WKLV�ZLWK�D�VLPSOH�H[WHUQDO�WLPHU��%XW�ZKDW�LI�WKH�SURFHVV�LQFOXGHG����VZLWFKHV�DQG

VROHQRLGV"�:H� ZRXOG� QHHG� ��� H[WHUQDO� WLPHUV��:KDW� LI� WKH� SURFHVV� DOVR� QHHGHG� WR

FRXQW�KRZ�PDQ\�WLPHV�WKH�VZLWFKHV�LQGLYLGXDOO\�WXUQHG�RQ"�:H�QHHG�D�ORW�RI�H[WHUQDO

FRXQWHUV��$V�\RX�FDQ�VHH�WKH�ELJJHU�WKH�SURFHVV�WKH�PRUH�RI�D�QHHG�ZH�KDYH�IRU�D�3/&�

:H�FDQ�VLPSO\�SURJUDP�WKH�3/&�WR�FRXQW�LWV�LQSXWV�DQG�WXUQ�WKH�VROHQRLGV�RQ�IRU�WKH

VSHFLILHG� WLPH�� ,�EHOLHYH� WKLV� WXWRULDO�ZLOO�JLYH�\RX�HQRXJK� LQIRUPDWLRQ� WR�EH�DEOH� WR

ZULWH�SURJUDPV�IDU�PRUH�FRPSOLFDWHG�WKDQ�WKLV�

3/&�KLVWRU\KWWS���ZZZ�SOFV�QHW�KLVWRU\��KWP

,Q�WKH�ODWH�����V�3/&V�ZHUH�ILUVW�LQWURGXFHG��7KH�SULPDU\�UHDVRQ�IRU�GHVLJQLQJ�VXFK�D

GHYLFH�ZDV�HOLPLQDWLQJ�WKH�VXEVWDQWLDO�FRVW�LQYROYHG�LQ�UHSODFLQJ�WKH�FRPSOLFDWHG�UHOD\

EDVHG� PDFKLQH� FRQWURO� V\VWHPV�� %HGIRUG� $VVRFLDWHV� �%HGIRUG�� 0$�� SURSRVHG

VRPHWKLQJ� FDOOHG� D� 0RGXODU� 'LJLWDO� &RQWUROOHU� �02',&21�� WR� D� PDMRU� 86� FDU

PDQXIDFWXUHU��2WKHU�FRPSDQLHV�DW�WKH�WLPH�SURSRVHG�FRPSXWHU�EDVHG�VFKHPHV��RQH�RI

ZKLFK�ZDV�EDVHG�XSRQ�WKH�3'3����7KH�02',&21�����EURXJKW�WKH�ZRUOGV�ILUVW�3/&

LQWR�FRPPHUFLDO�SURGXFWLRQ�

:KHQ�SURGXFWLRQ�UHTXLUHPHQWV�FKDQJHG�VR�GLG�WKH�FRQWURO�V\VWHP��7KLV�EHFRPHV�YHU\

H[SHQVLYH�ZKHQ�WKH�FKDQJH�LV�IUHTXHQW��6LQFH�UHOD\V�DUH�PHFKDQLFDO�GHYLFHV�WKH\�DOVR

KDYH� D� OLPLWHG� OLIHWLPH� ZKLFK� UHTXLUHG� VWULFW� DGKHVLRQ� WR� PDLQWHQDQFH� VFKHGXOHV�

7URXEOHVKRRWLQJ�ZDV�DOVR�TXLWH�WHGLRXV�ZKHQ�VR�PDQ\�UHOD\V�DUH�LQYROYHG�

Page 6: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH � ���� 3/& 78725

1RZ� SLFWXUH� D� PDFKLQH� FRQWURO� SDQHO� WKDW� LQFOXGHG� PDQ\�� SRVVLEO\� KXQGUHGV� RU

WKRXVDQGV�� RI� LQGLYLGXDO� UHOD\V�� 7KH� VL]H� FRXOG� EH� PLQG� ERJJOLQJ�� +RZ� DERXW� WKH

FRPSOLFDWHG� LQLWLDO� ZLULQJ� RI� VR� PDQ\� LQGLYLGXDO� GHYLFHV�� 7KHVH� UHOD\V� ZRXOG� EH

LQGLYLGXDOO\�ZLUHG� WRJHWKHU� LQ�D�PDQQHU� WKDW�ZRXOG�\LHOG� WKH�GHVLUHG�RXWFRPH��:HUH

WKHUH�SUREOHPV"�<RX�EHW��

7KHVH��QHZ�FRQWUROOHUV��DOVR�KDG�WR�EH�HDVLO\�SURJUDPPHG�E\�PDLQWHQDQFH�DQG�SODQW

HQJLQHHUV�� 7KH� OLIHWLPH� KDG� WR� EH� ORQJ� DQG� SURJUDPPLQJ� FKDQJHV� HDVLO\� SHUIRUPHG�

7KH\�DOVR�KDG� WR� VXUYLYH� WKH� KDUVK� LQGXVWULDO� HQYLURQPHQW��7KDWV� D� ORW� WR� DVN���7KH

DQVZHUV�ZHUH�WR�XVH�D�SURJUDPPLQJ�WHFKQLTXH�PRVW�SHRSOH�ZHUH�DOUHDG\�IDPLOLDU�ZLWK

DQG�UHSODFH�PHFKDQLFDO�SDUWV�ZLWK�VROLG�VWDWH�RQHV�

,Q�WKH�PLG��V�WKH�GRPLQDWH�3/&�WHFKQRORJLHV�ZHUH�VHTXHQFHU�VWDWH�PDFKLQHV�DQG�WKH

ELW�VOLFH�EDVHG�&38��7KH�$0'������DQG������ZHUH�TXLWH�SRSXODU�LQ�0RGLFRQ�DQG�$�

%�3/&V��&RQYHQWLRQDO�PLFURSURFHVVRUV�ODFNHG�WKH�SRZHU�WR�TXLFNO\�VROYH�3/&�ORJLF

LQ� DOO� EXW� WKH� VPDOOHVW� 3/&V�� $V� FRQYHQWLRQDO� PLFURSURFHVVRUV� HYROYHG�� ODUJHU� DQG

ODUJHU�3/&V�ZHUH�EHLQJ�EDVHG�XSRQ�WKHP��+RZHYHU��HYHQ�WRGD\�VRPH�DUH�VWLOO�EDVHG

XSRQ� WKH������� �UHI�$�%V�3/&����0RGLFRQ�KDV�\HW� WR�EXLOG� D� IDVWHU� 3/&� WKDQ� WKHLU

���$�%�;�ZKLFK�ZDV�EDVHG�XSRQ�WKH������

&RPPXQLFDWLRQV� DELOLWLHV� EHJDQ� WR� DSSHDU� LQ� DSSUR[LPDWHO\� ������ 7KH� ILUVW� VXFK

V\VWHP� ZDV�0RGLFRQV� 0RGEXV�� 7KH� 3/&� FRXOG� QRZ� WDON� WR� RWKHU� 3/&V� DQG� WKH\

FRXOG�EH�IDU�DZD\�IURP�WKH�DFWXDO�PDFKLQH�WKH\�ZHUH�FRQWUROOLQJ��7KH\�FRXOG�DOVR�QRZ

EH�XVHG�WR�HPLW�DQG�UHFHLYH�YDU\LQJ�YROWDJHV�WR�DOORZ�WKHP�WR�HQWHU�WKH�DQDORJ�ZRUOG�

8QIRUWXQDWHO\�� WKH� ODFN� RI� VWDQGDUGL]DWLRQ� FRXSOHG� ZLWK� FRQWLQXDOO\� FKDQJLQJ

WHFKQRORJ\�KDV�PDGH�3/&�FRPPXQLFDWLRQV�D�QLJKWPDUH�RI�LQFRPSDWLEOH�SURWRFROV�DQG

SK\VLFDO�QHWZRUNV��6WLOO��LW�ZDV�D�JUHDW�GHFDGH�IRU�WKH�3/&��

7KH� ��V� VDZ� DQ� DWWHPSW� WR� VWDQGDUL]H� FRPPXQLFDWLRQV� ZLWK� *HQHUDO� 0RWRUV

PDQXIDFWXULQJ�DXWRPDWLRQ�SURWRFRO��0$3���,W�ZDV�DOVR�D�WLPH�IRU�UHGXFLQJ�WKH�VL]H�RI

WKH�3/&�DQG�PDNLQJ�WKHP�VRIWZDUH�SURJUDPPDEOH�WKURXJK�V\PEROLF�SURJUDPPLQJ�RQ

SHUVRQDO� FRPSXWHUV� LQVWHDG� RI� GHGLFDWHG� SURJUDPPLQJ� WHUPLQDOV� RU� KDQGKHOG

SURJUDPPHUV�� 7RGD\� WKH�ZRUOGV� VPDOOHVW� 3/&� LV� DERXW� WKH� VL]H� RI� D� VLQJOH� FRQWURO

UHOD\����UHI�.H\HQFHV�.9�����

7KH���V�KDYH�VHHQ�D�JUDGXDO�UHGXFWLRQ�LQ� WKH�LQWURGXFWLRQ�RI�QHZ�SURWRFROV��DQG� WKH

PRGHUQL]DWLRQ� RI� WKH� SK\VLFDO� OD\HUV� RI� VRPH� RI� WKH� PRUH� SRSXODU� SURWRFROV� WKDW

VXUYLYHG� WKH� ����V�� 7KH� ODWHVW� VWDQGDUG� �,(&� �������� KDV� WULHG� WR� PHUJH� SOF

SURJUDPPLQJ�ODQJXDJHV�XQGHU�RQH�LQWHUQDWLRQDO�VWDQGDUG��:H�QRZ�KDYH�3/&V�WKDW�DUH

SURJUDPPDEOH�LQ�IXQFWLRQ�EORFN�GLDJUDPV��LQVWUXFWLRQ�OLVWV��&�DQG�VWUXFWXUHG�WH[W�DOO�DW

WKH�VDPH�WLPH��

3&V�DUH�DOVR�EHLQJ�XVHG�WR�UHSODFH�3/&V�LQ�VRPH�DSSOLFDWLRQV��7KH�RULJLQDO�FRPSDQ\

ZKR�FRPPLVVLRQHG� WKH�02',&21�����KDV�DFWXDOO\�VZLWFKHG� WR�D�3&�EDVHG�FRQWURO

V\VWHP��:KDW�ZLOO�WKH���V�EULQJ"�2QO\�WLPH�ZLOO�WHOO�

Page 7: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH �

7KH�,QWHUQDOVKWWS���ZZZ�SOFV�QHW�SDUWV��KWP

7KH�3/&�PDLQO\�FRQVLVWV�RI�D�&38��PHPRU\�DUHDV��DQG�DSSURSULDWH�FLUFXLWV�WR�UHFHLYH

LQSXW�RXWSXW�GDWD��:H�FDQ�DFWXDOO\�FRQVLGHU� WKH�3/&�WR�EH�D�ER[�IXOO�RI�KXQGUHGV�RU

WKRXVDQGV� RI� VHSDUDWH� UHOD\V�� FRXQWHUV�� WLPHUV� DQG� GDWD� VWRUDJH� ORFDWLRQV�� 'R� WKHVH

FRXQWHUV��WLPHUV��HWF��UHDOO\�H[LVW"�1R��WKH\�GRQW��SK\VLFDOO\��H[LVW�EXW�UDWKHU�WKH\�DUH

VLPXODWHG�DQG�FDQ�EH�FRQVLGHUHG�VRIWZDUH�FRXQWHUV�� WLPHUV��HWF��7KHVH� LQWHUQDO� UHOD\V

DUH�VLPXODWHG�WKURXJK�ELW�ORFDWLRQV�LQ�UHJLVWHUV���PRUH�RQ�WKDW�ODWHU�

:KDW�GRHV�HDFK�SDUW�GR"

,1387�5(/$<6�7KHVH�DUH�FRQQHFWHG�WR�WKH�RXWVLGH�ZRUOG��7KH\�SK\VLFDOO\�H[LVW�DQG

UHFHLYH�VLJQDOV�IURP�VZLWFKHV��VHQVRUV��HWF��7\SLFDOO\�WKH\�DUH�QRW�UHOD\V�EXW�UDWKHU�WKH\

DUH�WUDQVLVWRUV�

,17(51$/�87,/,7<�5(/$<6��7KHVH�GR�QRW�UHFHLYH�VLJQDOV�IURP�WKH�RXWVLGH�ZRUOG

QRU�GR�WKH\�SK\VLFDOO\�H[LVW��7KH\�DUH�VLPXODWHG�UHOD\V�DQG�DUH�ZKDW�HQDEOHV�D�3/&�WR

HOLPLQDWH� H[WHUQDO� UHOD\V�� 7KHUH� DUH� DOVR� VRPH� VSHFLDO� UHOD\V� WKDW� DUH� GHGLFDWHG� WR

SHUIRUPLQJ�RQO\�RQH�WDVN��6RPH�DUH�DOZD\V�RQ�ZKLOH�VRPH�DUH�DOZD\V�RII��6RPH�DUH�RQ

RQO\�RQFH�GXULQJ�SRZHU�RQ�DQG�DUH�W\SLFDOO\�XVHG�IRU�LQLWLDOL]LQJ�GDWD�WKDW�ZDV�VWRUHG�

&2817(56�7KHVH� DJDLQ� GR� QRW� SK\VLFDOO\� H[LVW�� 7KH\� DUH� VLPXODWHG� FRXQWHUV� DQG

WKH\�FDQ�EH�SURJUDPPHG�WR�FRXQW�SXOVHV��7\SLFDOO\�WKHVH�FRXQWHUV�FDQ�FRXQW�XS��GRZQ

RU�ERWK�XS�DQG�GRZQ��6LQFH�WKH\�DUH�VLPXODWHG�WKH\�DUH�OLPLWHG�LQ�WKHLU�FRXQWLQJ�VSHHG�

6RPH�PDQXIDFWXUHUV�DOVR�LQFOXGH�KLJK�VSHHG�FRXQWHUV�WKDW�DUH�KDUGZDUH�EDVHG��:H�FDQ

WKLQN�RI�WKHVH�DV�SK\VLFDOO\�H[LVWLQJ��0RVW�WLPHV�WKHVH�FRXQWHUV�FDQ�FDQ�XS��GRZQ�RU�XS

DQG�GRZQ�

7,0(56�7KHVH� DOVR� GR� QRW� SK\VLFDOO\� H[LVW�� 7KH\� FRPH� LQ� PDQ\� YDULHWLHV� DQG

LQFUHPHQWV��7KH�PRVW�FRPPRQ�W\SH�LV�DQ�RQ�GHOD\�W\SH��2WKHUV�LQFOXGH�RII�GHOD\�DQG

ERWK�UHWHQWLYH�DQG�QRQ�UHWHQWLYH�W\SHV��,QFUHPHQWV�YDU\�IURP��PV�WKURXJK��V�

287387�5(/$<6�7KHVH�DUH�FRQQHFWHG� WR� WKH�RXWVLGH�ZRUOG��7KH\�SK\VLFDOO\�H[LVW

DQG� VHQG� RQ�RII� VLJQDOV� WR� VROHQRLGV�� OLJKWV�� HWF�� 7KH\� FDQ� EH� WUDQVLVWRUV�� UHOD\V�� RU

WULDFV�GHSHQGLQJ�XSRQ�WKH�PRGHO�FKRVHQ�

'$7$�6725$*(�7\SLFDOO\� WKHUH� DUH� UHJLVWHUV� DVVLJQHG� WR� VLPSO\� VWRUH� GDWD�� 7KH\

DUH�XVXDOO\�XVHG� DV� WHPSRUDU\� VWRUDJH� IRU�PDWK� RU� GDWD�PDQLSXODWLRQ��7KH\� FDQ� DOVR

Page 8: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH � ���� 3/& 78725

W\SLFDOO\�EH�XVHG�WR�VWRUH�GDWD�ZKHQ�SRZHU�LV�UHPRYHG�IURP�WKH�3/&��8SRQ�SRZHU�XS

WKH\�ZLOO�VWLOO�KDYH�WKH�VDPH�FRQWHQWV�DV�EHIRUH�SRZHU�ZDV�UHPRYHG��9HU\�FRQYHQLHQW

DQG�QHFHVVDU\��

+RZ�LW�:RUNVKWWS���ZZZ�SOFV�QHW�KRZZRUNV��KWP

$�3/&�ZRUNV�E\�FRQWLQXDOO\�VFDQQLQJ�D�SURJUDP��:H�FDQ�WKLQN�RI�WKLV�VFDQ�F\FOH�DV

FRQVLVWLQJ�RI���LPSRUWDQW�VWHSV��7KHUH�DUH�W\SLFDOO\�PRUH�WKDQ���EXW�ZH�FDQ�IRFXV�RQ

WKH�LPSRUWDQW�SDUWV�DQG�QRW�ZRUU\�DERXW�WKH�RWKHUV��7\SLFDOO\�WKH�RWKHUV�DUH�FKHFNLQJ

WKH�V\VWHP�DQG�XSGDWLQJ�WKH�FXUUHQW�LQWHUQDO�FRXQWHU�DQG�WLPHU�YDOXHV�

6WHS� ��&+(&.� ,1387� 67$786�)LUVW� WKH� 3/&� WDNHV� D� ORRN� DW� HDFK� LQSXW� WR

GHWHUPLQH�LI�LW�LV�RQ�RU�RII��,Q�RWKHU�ZRUGV��LV�WKH�VHQVRU�FRQQHFWHG�WR�WKH�ILUVW�LQSXW�RQ"

+RZ� DERXW� WKH� VHFRQG� LQSXW"� +RZ� DERXW� WKH� WKLUG���� ,W� UHFRUGV� WKLV� GDWD� LQWR� LWV

PHPRU\�WR�EH�XVHG�GXULQJ�WKH�QH[W�VWHS�

6WHS���(;(&87(�352*5$0�1H[W�WKH�3/&�H[HFXWHV�\RXU�SURJUDP�RQH�LQVWUXFWLRQ

DW�D�WLPH��0D\EH�\RXU�SURJUDP�VDLG�WKDW�LI�WKH�ILUVW�LQSXW�ZDV�RQ�WKHQ�LW�VKRXOG�WXUQ�RQ

WKH�ILUVW�RXWSXW��6LQFH�LW�DOUHDG\�NQRZV�ZKLFK�LQSXWV�DUH�RQ�RII�IURP�WKH�SUHYLRXV�VWHS

LW�ZLOO�EH�DEOH�WR�GHFLGH�ZKHWKHU�WKH�ILUVW�RXWSXW�VKRXOG�EH�WXUQHG�RQ�EDVHG�RQ�WKH�VWDWH

RI�WKH�ILUVW�LQSXW��,W�ZLOO�VWRUH�WKH�H[HFXWLRQ�UHVXOWV�IRU�XVH�ODWHU�GXULQJ�WKH�QH[W�VWHS�

6WHS� ��83'$7(� 287387� 67$786�)LQDOO\� WKH� 3/&� XSGDWHV� WKH� VWDWXV� RI� WKH

RXWSXWV��,W�XSGDWHV�WKH�RXWSXWV�EDVHG�RQ�ZKLFK�LQSXWV�ZHUH�RQ�GXULQJ�WKH�ILUVW�VWHS�DQG

WKH�UHVXOWV�RI�H[HFXWLQJ�\RXU�SURJUDP�GXULQJ�WKH�VHFRQG�VWHS��%DVHG�RQ�WKH�H[DPSOH�LQ

VWHS��� LW�ZRXOG�QRZ�WXUQ�RQ� WKH� ILUVW�RXWSXW�EHFDXVH� WKH� ILUVW� LQSXW�ZDV�RQ�DQG�\RXU

SURJUDP�VDLG�WR�WXUQ�RQ�WKH�ILUVW�RXWSXW�ZKHQ�WKLV�FRQGLWLRQ�LV�WUXH�

$IWHU�WKH�WKLUG�VWHS�WKH�3/&�JRHV�EDFN�WR�VWHS�RQH�DQG�UHSHDWV�WKH�VWHSV�FRQWLQXRXVO\�

2QH�VFDQ�WLPH�LV�GHILQHG�DV�WKH�WLPH�LW�WDNHV�WR�H[HFXWH�WKH���VWHSV�OLVWHG�DERYH�

Page 9: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH �

5HVSRQVH�7LPHKWWS���ZZZ�SOFV�QHW�UHVSRQVH��KWP

7KH�WRWDO�UHVSRQVH�WLPH�RI�WKH�3/&�LV�D�IDFW�ZH�KDYH�WR�FRQVLGHU�ZKHQ�VKRSSLQJ�IRU�D

3/&��-XVW�OLNH�RXU�EUDLQV��WKH�3/&�WDNHV�D�FHUWDLQ�DPRXQW�RI�WLPH�WR�UHDFW�WR�FKDQJHV�

,Q�PDQ\�DSSOLFDWLRQV�VSHHG�LV�QRW�D�FRQFHUQ��LQ�RWKHUV�WKRXJK���

,I�\RX�WDNH�D�PRPHQW�WR�ORRN�DZD\�IURP�\RXU�PRQLWRU�\RX�PLJKW�VHH�D�SLFWXUH�RQ�WKH

ZDOO��<RXU�H\HV�DFWXDOO\�VHH�WKH�SLFWXUH�EHIRUH�\RXU�EUDLQ�VD\V��2K��WKHUHV�D�SLFWXUH�RQ

WKH� ZDOO��� ,Q� WKLV� H[DPSOH� \RXU� H\HV� FDQ� EH� FRQVLGHUHG� WKH� VHQVRU�� 7KH� H\HV� DUH

FRQQHFWHG� WR� WKH� LQSXW� FLUFXLW� RI� \RXU� EUDLQ�� 7KH� LQSXW� FLUFXLW� RI� \RXU� EUDLQ� WDNHV� D

FHUWDLQ� DPRXQW� RI� WLPH� WR� UHDOL]H� WKDW� \RXU� H\HV� VDZ� VRPHWKLQJ�� �,I� \RX� KDYH� EHHQ

GULQNLQJ� DOFRKRO� WKLV� LQSXW� UHVSRQVH� WLPH� ZRXOG� EH� ORQJHU��� (YHQWXDOO\� \RXU� EUDLQ

UHDOL]HV�WKDW�WKH�H\HV�KDYH�VHHQ�VRPHWKLQJ�DQG�LW�SURFHVVHV�WKH�GDWD��,W� WKHQ�VHQGV�DQ

RXWSXW�VLJQDO�WR�\RXU�PRXWK��<RXU�PRXWK�UHFHLYHV�WKLV�GDWD�DQG�EHJLQV�WR�UHVSRQG�WR�LW�

(YHQWXDOO\�\RXU�PRXWK�XWWHUV�WKH�ZRUGV��*HH��WKDWV�D�UHDOO\�XJO\�SLFWXUH���

1RWLFH�LQ�WKLV�H[DPSOH�ZH�KDG�WR�UHVSRQG�WR���WKLQJV�

,1387��,W�WRRN�D�FHUWDLQ�DPRXQW�RI�WLPH�IRU�WKH�EUDLQ�WR�QRWLFH�WKH�LQSXW�VLJQDO�IURP

WKH�H\HV�

(;(&87,21�� ,W� WRRN� D� FHUWDLQ� DPRXQW�RI� WLPH� WR� SURFHVV� WKH� LQIRUPDWLRQ� UHFHLYHG

IURP�WKH�H\HV��&RQVLGHU�WKH�SURJUDP�WR�EH��,I�WKH�H\HV�VHH�DQ�XJO\�SLFWXUH�WKHQ�RXWSXW

DSSURSULDWH�ZRUGV�WR�WKH�PRXWK�

287387��7KH�PRXWK� UHFHLYHV� D� VLJQDO� IURP� WKH�EUDLQ� DQG� HYHQWXDOO\� VSLWV� �QR� SXQ

LQWHQGHG��RXW�WKH�ZRUGV��*HH��WKDWV�D�UHDOO\�XJO\�SLFWXUH��

(IIHFWV�RI�5HVSRQVH�7LPHKWWS���ZZZ�SOFV�QHW�UHVSGHWDLOV��KWP

1RZ�WKDW�ZH�NQRZ�DERXW�UHVSRQVH�WLPH��KHUHV�ZKDW�LW�UHDOO\�PHDQV�WR�WKH�DSSOLFDWLRQ�

7KH�3/&�FDQ�RQO\�VHH�DQ�LQSXW� WXUQ�RQ�RII�ZKHQ�LWV� ORRNLQJ��,Q�RWKHU�ZRUGV�� LW�RQO\

ORRNV�DW�LWV�LQSXWV�GXULQJ�WKH�FKHFN�LQSXW�VWDWXV�SDUW�RI�WKH�VFDQ�

Page 10: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

,Q�WKH�GLDJUDP��LQSXW���LV�QRW�VHHQ�XQWLO�VFDQ����7KLV� LV�EHFDXVH�ZKHQ�LQSXW��� WXUQHG

RQ��VFDQ���KDG�DOUHDG\�ILQLVKHG�ORRNLQJ�DW�WKH�LQSXWV��,QSXW���LV�QRW�VHHQ�XQWLO�VFDQ���

7KLV�LV�DOVR�EHFDXVH�ZKHQ�WKH�LQSXW�WXUQHG�RQ�VFDQ���KDG�DOUHDG\�ILQLVKHG�ORRNLQJ�DW

WKH� LQSXWV�� ,QSXW� �� LV� QHYHU� VHHQ�� 7KLV� LV� EHFDXVH� ZKHQ� VFDQ� �� ZDV� ORRNLQJ� DW� WKH

LQSXWV��VLJQDO���ZDV�QRW�RQ�\HW��,W�WXUQV�RII�EHIRUH�VFDQ���ORRNV�DW�WKH�LQSXWV��7KHUHIRUH

VLJQDO���LV�QHYHU�VHHQ�E\�WKH�SOF��7R�DYRLG�WKLV�ZH�VD\�WKDW�WKH�LQSXW�VKRXOG�EH�RQ�IRU�DW

OHDVW���LQSXW�GHOD\�WLPH���RQH�VFDQ�WLPH�

%XW�ZKDW�LI�LW�ZHUH�QRW�SRVVLEOH�IRU�WKH�LQSXW�WR�EH�RQ�WKLV�ORQJ"�7KHQ�WKH�SOF�GRHVQW

VHH� WKH� LQSXW� WXUQ�RQ��7KHUHIRUH� LW� EHFRPHV� D� SDSHU�ZHLJKW����1RW� WUXH�����������������2I

FRXUVH�WKHUH�PXVW�EH�D�ZD\�WR�JHW�DURXQG�WKLV��$FWXDOO\�WKHUH�DUH���ZD\V�

3XOVH�VWUHWFK�IXQFWLRQ��7KLV�IXQFWLRQ�H[WHQGV�WKH�OHQJWK�RI�WKH�LQSXW�VLJQDO�XQWLO�WKH�SOF

ORRNV�DW�WKH�LQSXWV�GXULQJ�WKH�QH[W�VFDQ��L�H��LW�VWUHWFKHV�WKH�GXUDWLRQ�RI�WKH�SXOVH�

,QWHUUXSW� IXQFWLRQ��7KLV� IXQFWLRQ� LQWHUUXSWV� WKH� VFDQ� WR�SURFHVV� D� VSHFLDO� URXWLQH� WKDW

\RX� KDYH� ZULWWHQ�� L�H�� $V� VRRQ� DV� WKH� LQSXW� WXUQV� RQ�� UHJDUGOHVV� RI� ZKHUH� WKH� VFDQ

FXUUHQWO\�LV��WKH�SOF�LPPHGLDWHO\�VWRSV�ZKDW�LWV�GRLQJ�DQG�H[HFXWHV�DQ�LQWHUUXSW�URXWLQH�

�$�URXWLQH�FDQ�EH�WKRXJKW�RI�DV�D�PLQL�SURJUDP�RXWVLGH�RI�WKH�PDLQ�SURJUDP���$IWHU�LWV

GRQH� H[HFXWLQJ� WKH� LQWHUUXSW� URXWLQH�� LW� JRHV� EDFN� WR� WKH� SRLQW� LW� OHIW� RII� DW� DQG

FRQWLQXHV�RQ�ZLWK�WKH�QRUPDO�VFDQ�SURFHVV�

Page 11: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

1RZ�OHWV�FRQVLGHU�WKH�ORQJHVW�WLPH�IRU�DQ�RXWSXW�WR�DFWXDOO\�WXUQ�RQ��/HWV�DVVXPH�WKDW

ZKHQ�D� VZLWFK� WXUQV�RQ�ZH�QHHG� WR� WXUQ�RQ� D� ORDG� FRQQHFWHG� WR� WKH�SOF� RXWSXW��7KH

GLDJUDP�EHORZ�VKRZV�WKH�ORQJHVW�GHOD\��ZRUVW�FDVH�EHFDXVH�WKH�LQSXW�LV�QRW�VHHQ�XQWLO

VFDQ����IRU�WKH�RXWSXW�WR�WXUQ�RQ�DIWHU�WKH�LQSXW�KDV�WXUQHG�RQ��7KH�PD[LPXP�GHOD\�LV

WKXV���VFDQ�F\FOHV�����LQSXW�GHOD\�WLPH�

,WV�QRW�VR�GLIILFXOW��QRZ�LV�LW�"""""""

5(/$<6KWWS���ZZZ�SOFV�QHW�UHOD\V��KWP

1RZ� WKDW� ZH� XQGHUVWDQG� KRZ� WKH� 3/&� SURFHVVHV� LQSXWV�� RXWSXWV�� DQG� WKH� DFWXDO

SURJUDP�ZH�DUH�DOPRVW�UHDG\�WR�VWDUW�ZULWLQJ�D�SURJUDP��%XW�ILUVW�OHWV�VHH�KRZ�D�UHOD\

DFWXDOO\�ZRUNV��$IWHU�DOO��WKH�PDLQ�SXUSRVH�RI�D�SOF�LV�WR�UHSODFH��UHDO�ZRUOG��UHOD\V�

:H�FDQ�WKLQN�RI�D�UHOD\�DV�DQ�HOHFWURPDJQHWLF�VZLWFK��$SSO\�D�YROWDJH�WR�WKH�FRLO�DQG�D

PDJQHWLF� ILHOG� LV� JHQHUDWHG�� 7KLV� PDJQHWLF� ILHOG� VXFNV� WKH� FRQWDFWV� RI� WKH� UHOD\� LQ

FDXVLQJ�WKHP�WR�PDNH�D�FRQQHFWLRQ��7KHVH�FRQWDFWV�FDQ�EH�FRQVLGHUHG�WR�EH�D�VZLWFK�

7KH\�DOORZ�FXUUHQW�WR�IORZ�EHWZHHQ���SRLQWV�WKHUHE\�FORVLQJ�WKH�FLUFXLW�

/HWV�FRQVLGHU�WKH�IROORZLQJ�H[DPSOH��+HUH�ZH�VLPSO\�WXUQ�RQ�D�EHOO��/XQFK�WLPH�����

ZKHQHYHU�D�VZLWFK�LV�FORVHG��:H�KDYH���UHDO�ZRUOG�SDUWV��$�VZLWFK��D�UHOD\�DQG�D�EHOO�

:KHQHYHU�WKH�VZLWFK�FORVHV�ZH�DSSO\�D�FXUUHQW�WR�D�EHOO�FDXVLQJ�LW�WR�VRXQG�

Page 12: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

1RWLFH�LQ�WKH�SLFWXUH�WKDW�ZH�KDYH���VHSDUDWH�FLUFXLWV��7KH�UHG�LQGLFDWHV� WKH�'&�SDUW�

7KH�EOXH�LQGLFDWHV�WKH�$&�SDUW��+HUH�ZH�DUH�XVLQJ�D�GF�UHOD\�WR�FRQWURO�DQ�$&�FLUFXLW�

7KDWV�WKH�IXQ�RI�UHOD\V���:KHQ�WKH�VZLWFK�LV�RSHQ�QR�FXUUHQW�FDQ�IORZ�WKURXJK�WKH�FRLO

RI� WKH� UHOD\��$V�VRRQ�DV� WKH�VZLWFK� LV�FORVHG��KRZHYHU�� FXUUHQW� UXQV� WKURXJK� WKH�FRLO

FDXVLQJ� D�PDJQHWLF� ILHOG� WR� EXLOG� XS��7KLV�PDJQHWLF� ILHOG� FDXVHV� WKH� FRQWDFWV� RI� WKH

UHOD\� WR� FORVH�� 1RZ� $&� FXUUHQW� IORZV� WKURXJK� WKH� EHOO� DQG� ZH� KHDU� LW�� /XQFK

WLPH��������������

5HSODFLQJ�5HOD\VKWWS���ZZZ�SOFV�QHW�UHSODFH��KWP

1H[W�� OHWV� XVH� D� SOF� LQ� SODFH� RI� WKH� UHOD\�� �1RWH� WKDW� WKLV� PLJKW� QRW� EH� YHU\� FRVW

HIIHFWLYH� IRU� WKLV�DSSOLFDWLRQ�EXW� LW�GRHV�GHPRQVWUDWH� WKH�EDVLFV�ZH�GR�VR�QHHG���7KH

ILUVW� WKLQJ� WKDWV�QHFHVVDU\� LV� WR�FUHDWH�ZKDWV�FDOOHG�D� ODGGHU�GLDJUDP��$IWHU� VHHLQJ�D

IHZ�RI�WKHVH�LW�ZLOO�EHFRPH�REYLRXV�ZK\�LWV�FDOOHG�D�ODGGHU�GLDJUDP��:H�KDYH�WR�FUHDWH

RQH�RI�WKHVH�EHFDXVH��XQIRUWXQDWHO\��D�SOF�GRHVQW�XQGHUVWDQG�D�VFKHPDWLF�GLDJUDP��,W

RQO\� UHFRJQL]HV� FRGH�� )RUWXQDWHO\� PRVW� SOFV� KDYH� VRIWZDUH� ZKLFK� FRQYHUW� ODGGHU

GLDJUDPV�LQWR�FRGH��7KLV�VKLHOGV�XV�IURP�DFWXDOO\�OHDUQLQJ�WKH�SOFV�FRGH�

)LUVW� VWHS� ��:H� KDYH� WR� WUDQVODWH� DOO� RI� WKH� LWHPV� ZHUH� XVLQJ� LQWR� V\PEROV� WKH� SOF

XQGHUVWDQGV��7KH�SOF�GRHVQW� XQGHUVWDQG� WHUPV� OLNH� VZLWFK�� UHOD\�� EHOO�� HWF�� ,W� SUHIHUV

LQSXW��RXWSXW��FRLO��FRQWDFW��HWF��,W�GRHVQW�FDUH�ZKDW� WKH�DFWXDO� LQSXW�RU�RXWSXW�GHYLFH

DFWXDOO\�LV��,W�RQO\�FDUHV�WKDW�LWV�DQ�LQSXW�RU�DQ�RXWSXW��)LUVW�ZH�UHSODFH�WKH�EDWWHU\�ZLWK

D�V\PERO��7KLV�V\PERO�LV�FRPPRQ�WR�DOO�ODGGHU�GLDJUDPV��:H�GUDZ�ZKDW�DUH�FDOOHG�EXV

EDUV��7KHVH�VLPSO\�ORRN�OLNH�WZR�YHUWLFDO�EDUV��2QH�RQ�HDFK�VLGH�RI�WKH�GLDJUDP��7KLQN

RI�WKH�OHIW�RQH�DV�EHLQJ���YROWDJH�DQG�WKH�ULJKW�RQH�DV�EHLQJ�JURXQG��)XUWKHU�WKLQN�RI

WKH�FXUUHQW��ORJLF��IORZ�DV�EHLQJ�IURP�OHIW�WR�ULJKW��1H[W�ZH�JLYH�WKH�LQSXWV�D�V\PERO�

,Q�WKLV�EDVLF�H[DPSOH�ZH�KDYH�RQH�UHDO�ZRUOG�LQSXW���L�H��WKH�VZLWFK���:H�JLYH�WKH�LQSXW

WKDW�WKH�VZLWFK�ZLOO�EH�FRQQHFWHG�WR�WKH�V\PERO�

7KLV� V\PERO� FDQ� DOVR� EH� XVHG� DV� WKH� FRQWDFW� RI� D� UHOD\��1H[W�ZH� JLYH� WKH� RXWSXWV� D

V\PERO��,Q�WKLV�H[DPSOH�ZH�XVH�RQH�RXWSXW��L�H��WKH�EHOO���:H�JLYH�WKH�RXWSXW�WKDW�WKH

EHOO�ZLOO�EH�SK\VLFDOO\�FRQQHFWHG�WR�WKH�V\PERO�

Page 13: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

7KLV�V\PERO�LV�XVHG�DV�WKH�FRLO�RI�D�UHOD\��7KH�$&�VXSSO\�LV�DQ�H[WHUQDO�VXSSO\�VR�ZH

GRQW�SXW� LW� LQ�RXU� ODGGHU��7KH�SOF�RQO\�FDUHV�DERXW�ZKLFK�RXWSXW� LW� WXUQV�RQ�DQG�QRW

ZKDWV�SK\VLFDOO\�FRQQHFWHG�WR�LW��7KDWV�RXU�SUREOHP���

6HFRQG� VWHS� ��:H�PXVW� WHOO� WKH� SOF�ZKHUH� HYHU\WKLQJ� LV� ORFDWHG�� ,Q� RWKHU�ZRUGV�ZH

KDYH� WR� JLYH� DOO� WKH� GHYLFHV� DQ� DGGUHVV��:KHUH� LV� WKH� VZLWFK� JRLQJ� WR� EH� SK\VLFDOO\

FRQQHFWHG�WR�WKH�SOF"�+RZ�DERXW�WKH�EHOO"�:H�VWDUW�ZLWK�D�EODQN�URDG�PDS�LQ�WKH�SOFV

WRZQ�DQG�JLYH�HDFK�LWHP�DQ�DGGUHVV��&RXOG�\RX�ILQG�\RXU� IULHQGV� LI�\RX�GLGQW�NQRZ

WKHLU�DGGUHVV"�<RX�NQRZ�WKH\�OLYH�LQ�WKH�VDPH�WRZQ�EXW�ZKLFK�KRXVH"�7KH�SOF� WRZQ

KDV� D� ORW� RI� KRXVHV� �LQSXWV� DQG� RXWSXWV�� EXW�ZH� KDYH� WR� ILJXUH� RXW�ZKR� OLYHV�ZKHUH

�ZKDW�GHYLFH�LV�FRQQHFWHG�ZKHUH���:HOO�JHW�IXUWKHU� LQWR�WKH�DGGUHVVLQJ�VFKHPH�ODWHU�

(YHU\ERG\�GRHV�LW�D�GLIIHUHQW�ZD\����������)RU�QRZ�OHWV�VD\�WKDW�RXU�LQSXW�ZLOO�EH�FDOOHG

��������7KH�RXWSXW�ZLOO�EH�FDOOHG�������

)LQDO�VWHS���:H�KDYH�WR�FRQYHUW�WKH�VFKHPDWLF�LQWR�D�ORJLFDO�VHTXHQFH�RI�HYHQWV��7KLV�LV

PXFK�HDVLHU�WKDQ�LW�VRXQGV��7KH�SURJUDP�ZHUH�JRLQJ�WR�ZULWH�WHOOV�WKH�SOF�ZKDW�WR�GR

ZKHQ�FHUWDLQ�HYHQWV�WDNH�SODFH��,Q�RXU�H[DPSOH�ZH�KDYH�WR�WHOO�WKH�SOF�ZKDW�WR�GR�ZKHQ

WKH� RSHUDWRU� WXUQV� RQ� WKH� VZLWFK�� 2EYLRXVO\� ZH� ZDQW� WKH� EHOO� WR� VRXQG� EXW� WKH� SOF

GRHVQW�NQRZ�WKDW��,WV�D�SUHWW\�VWXSLG�GHYLFH��LVQW�LW���

7KLV�SLFWXUH� LV� WKH�ILQDO�FRQYHUWHG�GLDJUDP��1RWLFH�WKDW�ZH�HOLPLQDWHG�WKH� UHDO�ZRUOG

UHOD\� IURP� QHHGLQJ� D� V\PERO�� ,WV� DFWXDOO\� �LQIHUUHG�� IURP� WKH� GLDJUDP�� +XK"""""

'RQW�ZRUU\��\RXOO�VHH�ZKDW�,�PHDQ�DV�ZH�GR�PRUH�H[DPSOHV�

%DVLF�,QVWUXFWLRQVKWWS���ZZZ�SOFV�QHW�EDVLF��KWP

1RZ�OHWV�H[DPLQH�VRPH�RI� WKH�EDVLF� LQVWUXFWLRQV� LV�JUHDWHU�GHWDLO� WR� VHH�PRUH�DERXW

ZKDW�HDFK�RQH�GRHV�

/RDG

7KH�ORDG�LQVWUXFWLRQ�LV�D�QRUPDOO\�RSHQ�FRQWDFW�� ,W� LV�VRPHWLPHV�DOVR�FDOOHG�H[DPLQH

RQ�� �DV� LQ� H[DPLQH� WKH� LQSXW� WR� VHH� LI� LWV� SK\VLFDOO\� RQ��� 7KH� V\PERO� IRU� D� ORDG

LQVWUXFWLRQ�LV

Page 14: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

7KLV� LV�XVHG�ZKHQ�DQ�LQSXW�VLJQDO� LV�QHHGHG� WR�EH�SUHVHQW� IRU� WKH�V\PERO� WR� WXUQ�RQ�

:KHQ�WKH�SK\VLFDO�LQSXW�LV�2Q�ZH�FDQ�VD\�WKDW�WKH�LQVWUXFWLRQ�LV�7UXH��:H�H[DPLQH�WKH

LQSXW� IRU� DQ� RQ� VLJQDO�� ,I� WKH� LQSXW� LV� SK\VLFDOO\� RQ� WKHQ� WKH� V\PERO� LV� RQ�� $Q� RQ

FRQGLWLRQ�LV�DOVR�UHIHUUHG�WR�DV�D�ORJLF�����VWDWH��7KLV�V\PERO�QRUPDOO\�FDQ�EH�XVHG�IRU

LQWHUQDO� LQSXWV�� H[WHUQDO� LQSXWV�DQG�H[WHUQDO�RXWSXW� FRQWDFWV��5HPHPEHU� WKDW� LQWHUQDO

UHOD\V�GRQW�SK\VLFDOO\�H[LVW��7KH\�DUH�VLPXODWHG��VRIWZDUH��UHOD\V�

/RDG%DU

7KH� ORDGEDU� LQVWUXFWLRQ� LV� D� QRUPDOO\� FORVHG� FRQWDFW�� ,W� LV� VRPHWLPHV� DOVR� FDOOHG

ORDGQRW� RU� H[DPLQH� RII�� �DV� LQ� H[DPLQH� WKH� LQSXW� WR� VHH� LI� LWV� SK\VLFDOO\� RII��� 7KH

V\PERO�IRU�D�ORDGEDU�LQVWUXFWLRQ�LV

7KLV�LV�XVHG�ZKHQ�DQ�LQSXW�VLJQDO�GRHV�QRW�QHHG�WR�EH�SUHVHQW�IRU�WKH�V\PERO� WR� WXUQ

RQ��:KHQ�WKH�SK\VLFDO�LQSXW�LV�2II�ZH�FDQ�VD\�WKDW�WKH�LQVWUXFWLRQ�LV�7UXH��:H�H[DPLQH

WKH�LQSXW�IRU�DQ�RII�VLJQDO��,I�WKH�LQSXW�LV�SK\VLFDOO\�RII�WKHQ�WKH�V\PERO�LV�RQ��$Q�RII

FRQGLWLRQ�LV�DOVR�UHIHUUHG�WR�DV�D�ORJLF�����VWDWH��7KLV�V\PERO�QRUPDOO\�FDQ�EH�XVHG�IRU

LQWHUQDO� LQSXWV�� H[WHUQDO� LQSXWV� DQG� VRPHWLPHV� H[WHUQDO� RXWSXW� FRQWDFWV�� 5HPHPEHU

DJDLQ�WKDW�LQWHUQDO�UHOD\V�GRQW�SK\VLFDOO\�H[LVW��7KH\�DUH�VLPXODWHG��VRIWZDUH��UHOD\V��,W

LV�WKH�H[DFW�RSSRVLWH�RI�WKH�/RDG�LQVWUXFWLRQ�

127(��:LWK�PRVW�SOFV�WKLV�LQVWUXFWLRQ��/RDG�RU�/RDGEDU��0867�EH�WKH�ILUVW�V\PERO

RQ�WKH�OHIW�RI�WKH�ODGGHU�

/RJLF�6WDWH /RDG /RDG%DU

� )DOVH 7UXH

� 7UXH )DOVH

2XW

7KH� 2XW� LQVWUXFWLRQ� LV� VRPHWLPHV� DOVR� FDOOHG� DQ� 2XWSXW(QHUJL]H� LQVWUXFWLRQ�� 7KH

RXWSXW�LQVWUXFWLRQ�LV�OLNH�D�UHOD\�FRLO��,WV�V\PERO�ORRNV�OLNH�WKLV�

:KHQ�WKHUH�LV�D�SDWK�RI�7UXH�LQVWUXFWLRQV�SUHFHGLQJ�WKLV�RQ�WKH�ODGGHU�UXQJ��LW�ZLOO�DOVR

EH� 7UXH�� :KHQ� WKH� LQVWUXFWLRQ� LV� 7UXH� LW� LV� SK\VLFDOO\� 2Q�� :H� FDQ� WKLQN� RI� WKLV

LQVWUXFWLRQ�DV�D�QRUPDOO\�RSHQ�RXWSXW��7KLV� LQVWUXFWLRQ�FDQ�EH�XVHG�IRU� LQWHUQDO�FRLOV

DQG�H[WHUQDO�RXWSXWV�

Page 15: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

2XWEDU

7KH�2XWEDU�LQVWUXFWLRQ�LV�VRPHWLPHV�DOVR�FDOOHG�DQ�2XW1RW�LQVWUXFWLRQ��6RPH�YHQGRUV

GRQW�KDYH�WKLV�LQVWUXFWLRQ��7KH�RXWEDU�LQVWUXFWLRQ�LV�OLNH�D�QRUPDOO\�FORVHG�UHOD\�FRLO�

,WV�V\PERO�ORRNV�OLNH�WKLV�

:KHQ�WKHUH�LV�D�SDWK�RI�)DOVH�LQVWUXFWLRQV�SUHFHGLQJ�WKLV�RQ�WKH�ODGGHU�UXQJ��LW�ZLOO�EH

7UXH��:KHQ�WKH�LQVWUXFWLRQ�LV�7UXH�LW�LV�SK\VLFDOO\�2Q��:H�FDQ�WKLQN�RI�WKLV�LQVWUXFWLRQ

DV�D�QRUPDOO\�FORVHG�RXWSXW��7KLV�LQVWUXFWLRQ�FDQ�EH�XVHG�IRU�LQWHUQDO�FRLOV�DQG�H[WHUQDO

RXWSXWV��,W�LV�WKH�H[DFW�RSSRVLWH�RI�WKH�2XW�LQVWUXFWLRQ�

/RJLF�6WDWH 2XW 2XW%DU

� )DOVH 7UXH

� 7UXH )DOVH

%DVLF�3URJUDP�([DPSOHKWWS���ZZZ�SOFV�QHW�H[DPSOH���KWP

1RZ� OHWV� FRPSDUH� D� VLPSOH� ODGGHU� GLDJUDP� ZLWK� LWV� UHDO� ZRUOG� H[WHUQDO� SK\VLFDOO\

FRQQHFWHG�UHOD\�FLUFXLW�DQG�6((�WKH�GLIIHUHQFHV��,Q�WKH�DERYH�FLUFXLW��WKH�FRLO�ZLOO�EH

HQHUJL]HG�ZKHQ�WKHUH�LV�D�FORVHG�ORRS�EHWZHHQ�WKH���DQG���WHUPLQDOV�RI�WKH�EDWWHU\��:H

FDQ� VLPXODWH� WKLV� VDPH� FLUFXLW� ZLWK� D� ODGGHU� GLDJUDP��$� ODGGHU� GLDJUDP� FRQVLVWV� RI

LQGLYLGXDO�UXQJV�MXVW�OLNH�RQ�D�UHDO�ODGGHU��(DFK�UXQJ�PXVW�FRQWDLQ�RQH�RU�PRUH�LQSXWV

DQG� RQH� RU� PRUH� RXWSXWV�� 7KH� ILUVW� LQVWUXFWLRQ� RQ� D� UXQJ� PXVW� DOZD\V� EH� DQ� LQSXW

LQVWUXFWLRQ� DQG� WKH� ODVW� LQVWUXFWLRQ� RQ� D� UXQJ� VKRXOG� DOZD\V� EH� DQ� RXWSXW� �RU� LWV

HTXLYDOHQW��

1RWLFH�LQ� WKLV�VLPSOH�RQH�UXQJ�ODGGHU�GLDJUDP�ZH�KDYH�UHFUHDWHG� WKH�H[WHUQDO�FLUFXLW

DERYH� ZLWK� D� ODGGHU� GLDJUDP�� +HUH� ZH� XVHG� WKH� /RDG� DQG� 2XW� LQVWUXFWLRQV�� (YHU\

ODGGHU�GLDJUDP�PXVW� LQFOXGH� WKH�(1'�LQVWUXFWLRQ�RQ� WKH� ODVW� UXQJ��6RPH�3/&V�DOVR

Page 16: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

UHTXLUH�DQ�(1'+�LQVWUXFWLRQ�RQ�WKH�UXQJ�DIWHU�WKH�(1'�UXQJ��2Q�WKH�QH[W�SDJH�ZHOO

FKDQJH�WKH�VHFRQG�VZLWFK�WR�D�ORDGEDU��QRUPDOO\�FORVHG�W\SH��DQG�WUDFH�WKH�UHJLVWHUV�

5HJLVWHUV""�/HWV�VHH���

3/&�5HJLVWHUVKWWS���ZZZ�SOFV�QHW�UHJLVWHUV���KWP

:HOO� NQRZ� WDNH� WKH� SUHYLRXV� H[DPSOH� DQG� FKDQJH� VZLWFK� �� �6:��� WR� D� QRUPDOO\

FORVHG� LQSXW� �ORDGEDU� LQVWUXFWLRQ�� DQG� WUDFH� WKH� UHJLVWHUV�� 7KH� ODGGHU� GLDJUDP� QRZ

ORRNV�OLNH�WKLV�

1RWLFH�DOVR�WKDW�ZH�QRZ�JDYH�HDFK�V\PERO�RU�LQVWUXFWLRQ�DQ�DGGUHVV��7KLV�DGGUHVV�VHWV

DVLGH�D�FHUWDLQ�VWRUDJH�DUHD� LQ� WKH�SOFV�GDWD� ILOHV�VR� WKDW� WKH�VWDWXV�RI� WKH� LQVWUXFWLRQ

�L�H�� WUXH�IDOVH�� FDQ�EH� VWRUHG��0DQ\�SOFV� XVH���� VORW� RU� ELW� VWRUDJH� ORFDWLRQV�� ,Q� WKH

H[DPSOH�DERYH�ZH�DUH�XVLQJ�WZR�GLIIHUHQW�VWRUDJH�ORFDWLRQV�RU�UHJLVWHUV�

5(*,67(5���

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� �

5(*,67(5���

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

,Q�WKH�WDEOHV�DERYH�ZH�FDQ�VHH�WKDW�LQ�UHJLVWHU�����ELW�����L�H��LQSXW�������ZDV�D�ORJLF��

DQG�ELW�����L�H�� LQSXW�������ZDV�D� ORJLF����5HJLVWHU���� VKRZV� WKDW�ELW���� �L�H��RXWSXW

������ZDV�D�ORJLF����7KH�ORJLF���RU���LQGLFDWHV�ZKHWKHU�DQ�LQVWUXFWLRQ�LV�)DOVH�RU�7UXH�

$OWKRXJK�PRVW�RI�WKH�LWHPV�LQ�WKH�UHJLVWHU�WDEOHV�DERYH�DUH�HPSW\��WKH\�VKRXOG�HDFK

FRQWDLQ�D����,�OHIW�WKHP�EODQN�WR�HPSKDVL]H�WKH�ORFDWLRQV�ZH�ZHUH�FRQFHUQHG�ZLWK�

/2*,&$/�&21',7,21�2)�6<0%2/

/2*,&�%,76 /' /'% 287

/RJLF�� )DOVH 7UXH )DOVH

/RJLF�� 7UXH )DOVH 7UXH

7KH�SOF�ZLOO�RQO\�HQHUJL]H�DQ�RXWSXW�ZKHQ�DOO�FRQGLWLRQV�RQ�WKH�UXQJ�DUH�758(��6R�

ORRNLQJ�DW�WKH�WDEOH�DERYH��ZH�VHH�WKDW�LQ�WKH�SUHYLRXV�H[DPSOH�6:��KDV�WR�EH�ORJLF��

DQG�6:��PXVW�EH�ORJLF����7KHQ�DQG�21/<�WKHQ�ZLOO�WKH�FRLO�EH�WUXH��L�H��HQHUJL]HG���,I

Page 17: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

DQ\�RI� WKH� LQVWUXFWLRQV�RQ� WKH� UXQJ�EHIRUH� WKH�RXWSXW� �FRLO�� DUH� IDOVH� WKHQ� WKH�RXWSXW

�FRLO��ZLOO�EH�IDOVH��QRW�HQHUJL]HG��

/HWV� QRZ� ORRN� DW� D� WUXWK� WDEOH� RI� RXU� SUHYLRXV� SURJUDP� WR� IXUWKHU� LOOXVWUDWH� WKLV

LPSRUWDQW�SRLQW��2XU�WUXWK�WDEOH�ZLOO�VKRZ�$//�SRVVLEOH�FRPELQDWLRQV�RI�WKH�VWDWXV�RI

WKH�WZR�LQSXWV�

,QSXWV�2XWSXWV

6:���/'� 6:���/'%� &2,/��287�

)DOVH 7UXH )DOVH

)DOVH )DOVH )DOVH

7UXH 7UXH 7UXH

7UXH )DOVH )DOVH

5(*,67(5�/2*,&�%,76

6:���/'� 6:���/'%� &2,/��287�

� � �

� � �

� � �

� � �

1RWLFH� IURP� WKH� FKDUW� WKDW� DV� WKH� LQSXWV� FKDQJH� WKHLU� VWDWHV� RYHU� WLPH�� VR� ZLOO� WKH

RXWSXW��7KH�RXWSXW�LV�RQO\�WUXH��HQHUJL]HG��ZKHQ�DOO�SUHFHGLQJ�LQVWUXFWLRQV�RQ�WKH�UXQJ

DUH�WUXH��

/HYHO�$SSOLFDWLRQKWWS���ZZZ�SOFV�QHW�OHYHO���KWP

1RZ� WKDW� ZHYH� VHHQ� KRZ� UHJLVWHUV� ZRUN�� OHWV� SURFHVV� D� SURJUDP� OLNH� SOFV� GR� WR

HQKDQFH� RXU� XQGHUVWDQGLQJ� RI� KRZ� WKH� SURJUDP� JHWV� VFDQQHG�� /HWV� FRQVLGHU� WKH

IROORZLQJ�DSSOLFDWLRQ�

:H� DUH� FRQWUROOLQJ� OXEULFDWLQJ� RLO� EHLQJ� GLVSHQVHG� IURP� D� WDQN�� 7KLV� LV� SRVVLEOH� E\

XVLQJ�WZR�VHQVRUV��:H�SXW�RQH�QHDU�WKH�ERWWRP�DQG�RQH�QHDU�WKH�WRS��DV�VKRZQ�LQ�WKH

SLFWXUH�EHORZ�

Page 18: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

+HUH��ZH�ZDQW�WKH�ILOO�PRWRU�WR�SXPS�OXEULFDWLQJ�RLO�LQWR�WKH�WDQN�XQWLO�WKH�KLJK�OHYHO

VHQVRU�WXUQV�RQ��$W�WKDW�SRLQW�ZH�ZDQW�WR�WXUQ�RII�WKH�PRWRU�XQWLO�WKH�OHYHO�IDOOV�EHORZ

WKH� ORZ� OHYHO� VHQVRU��7KHQ�ZH� VKRXOG� WXUQ� RQ� WKH� ILOO�PRWRU� DQG� UHSHDW� WKH� SURFHVV�

+HUH�ZH�KDYH�D�QHHG�IRU���,�2��L�H��,QSXWV�2XWSXWV�����DUH�LQSXWV��WKH�VHQVRUV��DQG���LV

DQ�RXWSXW��WKH�ILOO�PRWRU��

%RWK�RI�RXU�LQSXWV�ZLOO�EH�1&��QRUPDOO\�FORVHG��ILEEHU�RSWLF�OHYHO�VHQVRUV��:KHQ�WKH\

DUH�127�LPPHUVHG�LQ�OLTXLG�WKH\�ZLOO�EH�21��:KHQ�WKH\�DUH�LPPHUVHG�LQ�OLTXLG�WKH\

ZLOO�EH�2))�

:H�ZLOO�JLYH�HDFK�LQSXW�DQG�RXWSXW�GHYLFH�DQ�DGGUHVV��7KLV� OHWV� WKH�SOF�NQRZ�ZKHUH

WKH\�DUH�SK\VLFDOO\�FRQQHFWHG��7KH�DGGUHVVHV�DUH�VKRZQ�LQ�WKH�IROORZLQJ�WDEOHV�

,13876 $''5(66 287387 $''5(66 ,17(51$/�87,/,7<�5(/$<

/RZ ���� 0RWRU ���� ����

+LJK ����

+HUH� LV�ZKDW� WKH� ODGGHU�GLDJUDP�ZLOO� DFWXDOO\� ORRN� OLNH��1RWLFH� WKDW�ZH�DUH�XVLQJ�DQ

LQWHUQDO�XWLOLW\�UHOD\�LQ�WKLV�H[DPSOH��<RX�FDQ�XVH�WKH�FRQWDFWV�RI�WKHVH�UHOD\V�DV�PDQ\

WLPHV�DV�UHTXLUHG��+HUH�WKH\�DUH�XVHG�WZLFH�WR�VLPXODWH�D�UHOD\�ZLWK���VHWV�RI�FRQWDFWV�

5HPHPEHU��WKHVH�UHOD\V�'2�127�SK\VLFDOO\�H[LVW�LQ�WKH�SOF�EXW�UDWKHU�WKH\�DUH�ELWV�LQ

D�UHJLVWHU�WKDW�\RX�FDQ�XVH�WR�6,08/$7(�D�UHOD\�

+RZ�D�/DGGHU�LV�6FDQQHGKWWS���ZZZ�SOFV�QHW�VFDQ���KWP

/HWV�ZDWFK�ZKDW� KDSSHQV� LQ� WKLV� SURJUDP� VFDQ� E\� VFDQ�� ,QLWLDOO\� WKH� WDQN� LV� HPSW\�

7KHUHIRUH��LQSXW������LV�758(�DQG�LQSXW������LV�DOVR�758(�

Page 19: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

�����������������6&$1����������������������������������������6&$1������

*UDGXDOO\� WKH� WDQN� ILOOV�EHFDXVH����� �ILOO�PRWRU�� LV� RQ��$IWHU� ���� VFDQV� WKH�RLO� OHYHO

ULVHV�DERYH�WKH�ORZ�OHYHO�VHQVRU�DQG�LW�EHFRPHV�RSHQ���L�H��)$/6(��

6&$1���������

1RWLFH� WKDW�HYHQ�ZKHQ� WKH� ORZ� OHYHO� VHQVRU� LV� IDOVH� WKHUH� LV� VWLOO� D�SDWK�RI� WUXH� ORJLF

IURP� OHIW� WR� ULJKW��7KLV� LV�ZK\�ZH�XVHG�DQ� LQWHUQDO� UHOD\��5HOD\������ LV� ODWFKLQJ� WKH

RXWSXW�������RQ��,W�ZLOO�VWD\�WKLV�ZD\�XQWLO�WKHUH�LV�QR�WUXH�ORJLF�SDWK�IURP�OHIW�WR�ULJKW�

�L�H��ZKHQ������EHFRPHV�IDOVH��

$IWHU������VFDQV�WKH�RLO�OHYHO�ULVHV�DERYH�WKH�KLJK�OHYHO�VHQVRU�DW�LW�DOVR�EHFRPHV�RSHQ

�L�H��IDOVH��

6&$1�����

Page 20: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

6&$1�����

6LQFH� WKHUH� LV�QR�PRUH� WUXH� ORJLF�SDWK�� RXWSXW����� LV� QR� ORQJHU� HQHUJL]HG� �WUXH�� DQG

WKHUHIRUH�WKH�PRWRU�WXUQV�RII��$IWHU������VFDQV�WKH�RLO�OHYHO�IDOOV�EHORZ�WKH�KLJK�OHYHO

VHQVRU�DQG�LW�ZLOO�EHFRPH�WUXH�DJDLQ�

6&$1�����

1RWLFH�WKDW�HYHQ�WKRXJK�WKH�KLJK�OHYHO�VHQVRU�EHFDPH�WUXH�WKHUH�VWLOO�LV�12�FRQWLQXRXV

WUXH�ORJLF�SDWK�DQG�WKHUHIRUH�FRLO������UHPDLQV�IDOVH����$IWHU������VFDQV�WKH�RLO�OHYHO

IDOOV�EHORZ�WKH�ORZ�OHYHO�VHQVRU�DQG�LW�ZLOO�DOVR�EHFRPH�WUXH�DJDLQ��$W� WKLV�SRLQW� WKH

ORJLF�ZLOO� DSSHDU� WKH� VDPH�DV�6&$1���DERYH�DQG� WKH� ORJLF�ZLOO� UHSHDW�DV� LOOXVWUDWHG

DERYH�

/DWFKLQJ�,QVWUXFWLRQVKWWS���ZZZ�SOFV�QHW�ODWFK���KWP

1RZ�WKDW�ZH�XQGHUVWDQG�KRZ�LQSXWV�DQG�RXWSXWV�DUH�SURFHVVHG�E\�WKH�SOF��OHWV�ORRN�DW

D�YDULDWLRQ�RI�RXU�UHJXODU�RXWSXWV��5HJXODU�RXWSXW�FRLOV�DUH�RI�FRXUVH�DQ�HVVHQWLDO�SDUW

RI� RXU� SURJUDPV� EXW� ZH� PXVW� UHPHPEHU� WKDW� WKH\� DUH� RQO\� 758(� ZKHQ� $//

,16758&7,216�EHIRUH�WKHP�RQ�WKH�UXQJ�DUH�DOVR�758(��:KDW�KDSSHQV�LI� WKH\�DUH

QRW"�7KHQ�RI�FRXUVH��WKH�RXWSXW�ZLOO�EHFRPH�IDOVH���WXUQ�RII�

7KLQN� EDFN� WR� WKH� OXQFK� EHOO� H[DPSOH� ZH� GLG� D� IHZ� FKDSWHUV� DJR�� :KDW� ZRXOGYH

KDSSHQHG�LI�ZH�FRXOGQW�ILQG�D��SXVK�RQ�SXVK�RII��VZLWFK"�7KHQ�ZH�ZRXOGYH�KDG� WR

NHHS�SUHVVLQJ� WKH�EXWWRQ� IRU�DV� ORQJ�DV�ZH�ZDQWHG� WKH�EHOO� WR� VRXQG�� �$�PRPHQWDU\

VZLWFK���7KH�ODWFKLQJ�LQVWUXFWLRQV�OHW�XV�XVH�PRPHQWDU\�VZLWFKHV�DQG�SURJUDP�WKH�SOF

Page 21: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

VR�WKDW�ZKHQ�ZH�SXVK�RQH�WKH�RXWSXW� WXUQV�RQ�DQG�ZKHQ�ZH�SXVK�DQRWKHU� WKH�RXWSXW

WXUQV�RII�

0D\EH�QRZ�\RXUH�VD\LQJ�WR�\RXUVHOI��:KDW� WKH�KHFN�LV�KH� WDONLQJ�DERXW"��� �,WV�DOVR

ZKDW� ,P� WKLQNLQJ���6R� OHWV� GR� D� UHDO�ZRUOG� H[DPSOH��3LFWXUH� WKH� UHPRWH� FRQWURO� IRU

\RXU�79�� ,W�KDV�D�EXWWRQ�IRU�21�DQG�DQRWKHU� IRU�2))�� �PLQH�GRHV�� DQ\ZD\��:KHQ� ,

SXVK�WKH�21�EXWWRQ�WKH�79�WXUQV�RQ��:KHQ�,�SXVK�WKH�2))�EXWWRQ�WKH�79�WXUQV�RII��,

GRQW� KDYH� WR� NHHS� SXVKLQJ� WKH� 21� EXWWRQ� WR� NHHS� WKH� 79� RQ�� 7KLV� ZRXOG� EH� WKH

IXQFWLRQ�RI�D�ODWFKLQJ�LQVWUXFWLRQ�

7KH� ODWFK� LQVWUXFWLRQ� LV� RIWHQ� FDOOHG� D� 6(7� RU� 27/� �RXWSXW� ODWFK��� 7KH� XQODWFK

LQVWUXFWLRQ� LV� RIWHQ� FDOOHG� D�5(6� �UHVHW���287� �RXWSXW� XQODWFK�� RU�567� �UHVHW��� 7KH

GLDJUDP�EHORZ�VKRZV�KRZ�WR�XVH�WKHP�LQ�D�SURJUDP�

+HUH�ZH�DUH�XVLQJ���PRPHQWDU\�SXVK�EXWWRQ�VZLWFKHV��2QH�LV�SK\VLFDOO\�FRQQHFWHG�WR

LQSXW������ZKLOH� WKH�RWKHU� LV�SK\VLFDOO\�FRQQHFWHG�WR� LQSXW�������:KHQ�WKH�RSHUDWRU

SXVKHV� VZLWFK� ����� WKH� LQVWUXFWLRQ� �VHW� ������ ZLOO� EHFRPH� WUXH� DQG� RXWSXW� ����

SK\VLFDOO\�WXUQV�RQ��(YHQ�DIWHU�WKH�RSHUDWRU�VWRSV�SXVKLQJ�WKH�VZLWFK��WKH�RXWSXW�������

ZLOO�UHPDLQ�RQ��,W�LV�ODWFKHG�RQ��7KH�RQO\�ZD\�WR�WXUQ�RII�RXWSXW������LV�WXUQ�RQ�LQSXW

������7KLV�ZLOO�FDXVH�WKH�LQVWUXFWLRQ��UHV�������WR�EHFRPH�WUXH�WKHUHE\�XQODWFKLQJ�RU

UHVHWWLQJ�RXWSXW������

+HUHV�VRPHWKLQJ�WR�WKLQN�DERXW��:KDW�ZRXOG�KDSSHQ�LI�LQSXW������DQG������ERWK�WXUQ

RQ�DW�WKH�H[DFW�VDPH�WLPH��:LOO�RXWSXW������EH�ODWFKHG�RU�XQODWFKHG""�7R�DQVZHU�WKLV

TXHVWLRQ�ZH�KDYH�WR�WKLQN�DERXW�WKH�VFDQQLQJ�VHTXHQFH��7KH�ODGGHU�LV�DOZD\V�VFDQQHG

IURP�WRS�WR�ERWWRP��OHIW�WR�ULJKW��7KH�ILUVW�WKLQJ�LQ�WKH�VFDQ�LV�WR�SK\VLFDOO\�ORRN�DW�WKH

LQSXWV�� ����� DQG� ����� DUH� ERWK� SK\VLFDOO\� RQ�� 1H[W� WKH� SOF� H[HFXWHV� WKH� SURJUDP�

6WDUWLQJ�IURP�WKH�WRS�OHIW��LQSXW������LV�WUXH�WKHUHIRUH�LW�VKRXOG�VHW�������1H[W�LW�JRHV

WR�WKH�QH[W�UXQJ�DQG�VLQFH�LQSXW������LV�WUXH�LW�VKRXOG�UHVHW�������7KH�ODVW�WKLQJ�LW�VDLG

ZDV�WR�UHVHW�������7KHUHIRUH�RQ�WKH�ODVW�SDUW�RI�WKH�VFDQ�ZKHQ�LW�XSGDWHV�WKH�RXWSXWV�LW

ZLOO�NHHS������RII���L�H��UHVHW�������

0DNHV�EHWWHU�VHQVH�QRZ��GRHVQW�LW""

Page 22: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

&RXQWHUVKWWS���ZZZ�SOFV�QHW�FRXQW���KWP

$� FRXQWHU� LV� D� VLPSOH� GHYLFH� LQWHQGHG� WR� GR� RQH� VLPSOH� WKLQJ�� FRXQW�� 8VLQJ� WKHP�

KRZHYHU�� FDQ� VRPHWLPHV� EH� D� FKDOOHQJH� EHFDXVH� HYHU\� PDQXIDFWXUHU� �IRU� ZKDWHYHU

UHDVRQ�� VHHPV� WR� XVH� WKHP� D� GLIIHUHQW� ZD\�� 5HVW� DVVXUHG� WKRXJK� WKDW� WKH� IROORZLQJ

LQIRUPDWLRQ�ZLOO�OHW�\RX�VLPSO\�DQG�HDVLO\�SURJUDP�DQ\ERGLHV�FRXQWHUV�

:KDW� NLQGV� RI� FRXQWHUV� DUH� WKHUH"�:HOO�� WKHUH� DUH� XS�FRXQWHUV� �WKH\� RQO\� FRXQW� XS

�����������7KHVH�DUH�FDOOHG�&78���FRXQW�XS��&17�&��RU�&75��7KHUH�DUH�GRZQ�FRXQWHUV

�WKH\�RQO\�FRXQW�GRZQ�������������7KHVH�DUH� W\SLFDOO\�FDOOHG�&7'��FRXQW�GRZQ��ZKHQ

WKH\�DUH�D�VHSHUDWH�LQVWUXFWLRQ�7KHUH�DUH�DOVR�XS�GRZQ�FRXQWHUV��WKH\�FRXQW�XS�DQG�RU

GRZQ� ������������������������ 7KHVH� DUH� W\SLFDOO\� FDOOHG�8'&� �XS�GRZQ� FRXQWHU��ZKHQ

WKH\� DUH� VHSDUDWH� LQVWUXFWLRQV�� 0DQ\� PDQXIDFWXUHUV� KDYH� RQO\� RQH� RU� WZR� W\SHV� RI

FRXQWHUV�EXW�WKH\�FDQ�EH�XVHG�WR�FRXQW�XS��GRZQ�RU�ERWK��&RQIXVHG�\HW"�&DQ�\RX�VD\

�QR� VWDQGDUGL]DWLRQ�"�'RQW�ZRUU\�� WKH� WKHRU\� LV� DOO� WKH� VDPH� UHJDUGOHVV� RI�ZKDW� WKH

PDQXIDFWXUHUV�FDOO�WKHP��$�FRXQWHU�LV�D�FRXQWHU�LV�D�FRXQWHU���

7R� IXUWKHU� FRQIXVH� WKH� LVVXH�� PRVW�PDQXIDFWXUHUV� DOVR� LQFOXGH� D� OLPLWHG� QXPEHU� RI

KLJK� VSHHG� FRXQWHUV�� 7KHVH� DUH� FRPPRQO\� FDOOHG� +6&� �KLJK�VSHHG� FRXQWHU��� &7+

�&RXQ7HU�+LJK�VSHHG"��RU�ZKDWHYHU��7\SLFDOO\�D�KLJK�VSHHG�FRXQWHU� LV� D� �KDUGZDUH�

GHYLFH��7KH� QRUPDO� FRXQWHUV� OLVWHG� DERYH� DUH� W\SLFDOO\� �VRIWZDUH�� FRXQWHUV�� ,Q� RWKHU

ZRUGV�WKH\�GRQW�SK\VLFDOO\�H[LVW�LQ�WKH�SOF�EXW�UDWKHU�WKH\�DUH�VLPXODWHG�LQ�VRIWZDUH�

+DUGZDUH�FRXQWHUV�GR�H[LVW�LQ�WKH�SOF�DQG�WKH\�DUH�QRW�GHSHQGHQW�RQ�VFDQ�WLPH��$�JRRG

UXOH�RI�WKXPE�LV�VLPSO\�WR�DOZD\V�XVH�WKH�QRUPDO��VRIWZDUH��FRXQWHUV�XQOHVV�WKH�SXOVHV

\RX�DUH�FRXQWLQJ�ZLOO�DUULYH�IDVWHU�WKDQ��;�WKH�VFDQ�WLPH���L�H��LI�WKH�VFDQ�WLPH�LV��PV

DQG� SXOVHV� ZLOO� EH� DUULYLQJ� IRU� FRXQWLQJ� HYHU\� �PV� RU� ORQJHU� WKHQ� XVH� D� VRIWZDUH

FRXQWHU��,I�WKH\�DUULYH�IDVWHU�WKDQ�HYHU\��PV���PV�IRU�H[DPSOH��WKHQ�XVH�WKH�KDUGZDUH

�KLJK�VSHHG��FRXQWHUV����[VFDQ�WLPH� ��[�PV� ��PV��

7R�XVH�WKHP�ZH�PXVW�NQRZ���WKLQJV�

��:KHUH�WKH�SXOVHV�WKDW�ZH�ZDQW�WR�FRXQW�DUH�FRPLQJ�IURP��7\SLFDOO\�WKLV�LV�IURP�RQH

RI�WKH�LQSXWV���D�VHQVRU�FRQQHFWHG�WR�LQSXW������IRU�H[DPSOH��

��+RZ�PDQ\�SXOVHV�ZH�ZDQW�WR�FRXQW�EHIRUH�ZH�UHDFW��/HWV�FRXQW���ZLGJHWV�EHIRUH�ZH

ER[�WKHP��IRU�H[DPSOH�

��:KHQ�KRZ�ZH�ZLOO�UHVHW�WKH�FRXQWHU�VR�LW�FDQ�FRXQW�DJDLQ��$IWHU�ZH�FRXQW���ZLGJHWV

OHWV�UHVHW�WKH�FRXQWHU��IRU�H[DPSOH�

:KHQ�WKH�SURJUDP�LV�UXQQLQJ�RQ�WKH�SOF�WKH�SURJUDP�W\SLFDOO\�GLVSOD\V�WKH�FXUUHQW�RU

�DFFXPXODWHG��YDOXH�IRU�XV�VR�ZH�FDQ�VHH�WKH�FXUUHQW�FRXQW�YDOXH��7\SLFDOO\�FRXQWHUV

FDQ�FRXQW�IURP���WR���������������WR���������RU���WR��������:K\�WKH�ZHLUG�QXPEHUV"

%HFDXVH� PRVW� SOFV� KDYH� ���ELW� FRXQWHUV��:HOO� JHW� LQWR� ZKDW� WKLV� PHDQV� LQ� D� ODWHU

FKDSWHU�EXW�IRU�QRZ�VXIILFH�LW�WR�VD\�WKDW��������LV����ELW�%&'��ELQDU\�FRGHG�GHFLPDO�

DQG�WKDW���������WR�������DQG���WR�������LV����ELW�ELQDU\�

Page 23: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

+HUH� DUH� VRPH� RI� WKH� LQVWUXFWLRQ� V\PEROV� ZH� ZLOO� HQFRXQWHU� �GHSHQGLQJ� RQ� ZKLFK

PDQXIDFWXUHU�ZH�FKRRVH��DQG�KRZ�WR�XVH�WKHP��5HPHPEHU�WKDW�ZKLOH� WKH\�PD\�ORRN

GLIIHUHQW� WKH\�DUH�DOO�XVHG�EDVLFDOO\� WKH�VDPH�ZD\�� ,I�ZH�FDQ�VHWXS�RQH�ZH�FDQ�VHWXS

DQ\�RI�WKHP�

,Q�WKLV�FRXQWHU�ZH�QHHG���LQSXWV��2QH�JRHV�EHIRUH�WKH�UHVHW�OLQH��:KHQ�WKLV�LQSXW�WXUQV

RQ�WKH�FXUUHQW��DFFXPXODWHG��FRXQW�YDOXH�ZLOO�UHWXUQ�WR�]HUR��7KH�VHFRQG�LQSXW� LV� WKH

DGGUHVV�ZKHUH� WKH� SXOVHV�ZH� DUH� FRXQWLQJ� DUH� FRPLQJ� IURP��)RU� H[DPSOH�� LI�ZH� DUH

FRXQWLQJ�KRZ�PDQ\�ZLGJHWV�SDVV�LQ�IURQW�RI�WKH�VHQVRU�WKDW�LV�SK\VLFDOO\�FRQQHFWHG�WR

LQSXW������WKHQ�ZH�ZRXOG�SXW�QRUPDOO\�RSHQ�FRQWDFWV�ZLWK�WKH�DGGUHVV������LQ�IURQW

RI� WKH�SXOVH� OLQH��&[[[� LV� WKH�QDPH�RI� WKH�FRXQWHU�� ,I�ZH�ZDQW� WR�FDOO� LW�FRXQWHU����

WKHQ� ZH� ZRXOG� SXW� �&����� KHUH�� \\\\\� LV� WKH� QXPEHU� RI� SXOVHV� ZH� ZDQW� WR� FRXQW

EHIRUH�GRLQJ�VRPHWKLQJ�� ,I�ZH�ZDQW� WR�FRXQW���ZLGJHWV�EHIRUH� WXUQLQJ�RQ�D�SK\VLFDO

RXWSXW�WR�ER[�WKHP�ZH�ZRXOG�SXW���KHUH��,I�ZH�ZDQWHG�WR�FRXQW�����ZLGJHWV�WKHQ�ZH

ZRXOG�SXW�����KHUH��HWF��:KHQ�WKH�FRXQWHU�LV�ILQLVKHG��L�H�ZH�FRXQWHG�\\\\\�ZLGJHWV�

LW�ZLOO�WXUQ�RQ�D�VHSHUDWH�VHW�RI�FRQWDFWV�WKDW�ZH�DOVR�ODEHO�&[[[��1RWH�WKDW�WKH�FRXQWHU

DFFXPXODWHG�YDOXH�21/<�FKDQJHV�DW�WKH�RII�WR�RQ�WUDQVLWLRQ�RI�WKH�SXOVH�LQSXW�

+HUHV�WKH�V\PERO�RQ�D�ODGGHU�VKRZLQJ�KRZ�ZH�VHW�XS�D�FRXQWHU��ZHOO�QDPH�LW�FRXQWHU

�����WR�FRXQW�����ZLGJHWV�IURP�LQSXW������EHIRUH�WXUQLQJ�RQ�RXWSXW������6HQVRU�����

UHVHWV�WKH�FRXQWHU�

+HUHV� RQH� V\PERO� ZH�PD\� HQFRXQWHU� IRU� DQ� XS�GRZQ� FRXQWHU��:HOO� XVH� WKH� VDPH

DEEUHYLDWLRQ�DV�ZH�GLG�IRU�WKH�H[DPSOH�DERYH���L�H��8'&[[[�DQG�\\\\\��

Page 24: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

,Q� WKLV� XS�GRZQ� FRXQWHU� ZH� QHHG� WR� DVVLJQ� �� LQSXWV�� 7KH� UHVHW� LQSXW� KDV� WKH� VDPH

IXQFWLRQ�DV�DERYH��+RZHYHU�� LQVWHDG�RI�KDYLQJ�RQO\�RQH�LQSXW�IRU� WKH�SXOVH�FRXQWLQJ

ZH�QRZ�KDYH� ���2QH� LV� IRU� FRXQWLQJ� XS� DQG� WKH� RWKHU� LV� IRU� FRXQWLQJ� GRZQ�� ,Q� WKLV

H[DPSOH�ZH�ZLOO�FDOO�WKH�FRXQWHU�8'&����DQG�ZH�ZLOO�JLYH�LW�D�SUHVHW�YDOXH�RI������

�ZHOO�FRXQW������WRWDO�SXOVHV���)RU�LQSXWV�ZHOO�XVH�D�VHQVRU�ZKLFK�ZLOO�WXUQ�RQ�LQSXW

�����ZKHQ�LW�VHHV�D�WDUJHW�DQG�DQRWKHU�VHQVRU�DW�LQSXW������ZLOO�DOVR�WXUQ�RQ�ZKHQ�LW

VHHV�D�WDUJHW��:KHQ�LQSXW������WXUQV�RQ�ZH�FRXQW�XS�DQG�ZKHQ�LQSXW������WXUQV�RQ�ZH

FRXQW�GRZQ��:KHQ�ZH�UHDFK������SXOVHV�ZH�ZLOO�WXUQ�RQ�RXWSXW������$JDLQ�QRWH�WKDW

WKH�FRXQWHU�DFFXPXODWHG�YDOXH�21/<�FKDQJHV�DW�WKH�RII�WR�RQ�WUDQVLWLRQ�RI�WKH�SXOVH

LQSXW�

+HUHV�WKH�ODGGHU�GLDJUDP�

2QH�LPSRUWDQW�WKLQJ�WR�QRWH�LV�WKDW�FRXQWHUV�DQG�WLPHUV�FDQW�KDYH�WKH�VDPH�QDPH��LQ

PRVW�SOFV���7KLV�LV�EHFDXVH�WKH\�W\SLFDOO\�XVH�WKH�VDPH�UHJLVWHUV��:H�KDYHQW� OHDUQHG

DERXW� WLPHUV� \HW� EXW� \RX�PLJKW�PDNH� D� QRWH� RI� WKLV� IRU� IXWXUH� UHIHUHQFH� EHFDXVH� LWV

SUHWW\�LPSRUWDQW�

:HOO��WKH�FRXQWHUV�DERYH�PLJKW�VHHP�GLIILFXOW�WR�XQGHUVWDQG�EXW�WKH\UH�DFWXDOO\�TXLWH

HDV\�RQFH�ZH�JHW�XVHG�WR�XVLQJ�WKHP��7KH\�FHUWDLQO\�DUH�DQ�HVVHQWLDO�WRRO�WR�PRVW�SOF

SURJUDPV�ZH�ZULWH��7KH\�DUH�DOVR�RQH�RI�WKH�OHDVW��VWDQGDUGL]HG��EDVLF�LQVWUXFWLRQV�WKDW

ZH�ZLOO�VHH��+RZHYHU��DOZD\V�UHPHPEHU�WKDW�WKH�WKHRU\�LV�WKH�VDPH�IURP�PDQXIDFWXUHU

WR�PDQXIDFWXUHU��

Page 25: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

7LPHUVKWWS���ZZZ�SOFV�QHW�WLPH���KWP

/HWV�QRZ�VHH�KRZ�D�WLPHU�ZRUNV��:KDW�LV�D�WLPHU"�,WV�H[DFWO\�ZKDW�WKH�ZRUG�VD\V����LW

LV� DQ� LQVWUXFWLRQ� WKDW� ZDLWV� D� VHW� DPRXQW� RI� WLPH� EHIRUH� GRLQJ� VRPHWKLQJ�� 6RXQGV

VLPSOH�GRHVQW�LW�

:KHQ�ZH� ORRN� DW� WKH� GLIIHUHQW� NLQGV� RI� WLPHUV� DYDLODEOH� WKH� IXQ� EHJLQV��$V� DOZD\V�

GLIIHUHQW�W\SHV�RI�WLPHUV�DUH�DYDLODEOH�ZLWK�GLIIHUHQW�PDQXIDFWXUHUV��+HUH�DUH�PRVW�RI

WKHP�

2Q�'HOD\� WLPHU�7KLV� W\SH�RI� WLPHU� VLPSO\� �GHOD\V� WXUQLQJ�RQ��� ,Q�RWKHU�ZRUGV�� DIWHU

RXU� VHQVRU� �LQSXW�� WXUQV� RQ� ZH� ZDLW� [�VHFRQGV� EHIRUH� DFWLYDWLQJ� D� VROHQRLG� YDOYH

�RXWSXW���7KLV�LV�WKH�PRVW�FRPPRQ�WLPHU��,W�LV�RIWHQ�FDOOHG�721��WLPHU�RQ�GHOD\���7,0

�WLPHU��RU�705��WLPHU��

2II�'HOD\�WLPHU��7KLV�W\SH�RI�WLPHU�LV�WKH�RSSRVLWH�RI�WKH�RQ�GHOD\�WLPHU�OLVWHG�DERYH�

7KLV�WLPHU�VLPSO\��GHOD\V�WXUQLQJ�RII���$IWHU�RXU�VHQVRU��LQSXW��VHHV�D� WDUJHW�ZH�WXUQ

RQ�D�VROHQRLG��RXWSXW���:KHQ�WKH�VHQVRU�QR�ORQJHU�VHHV�WKH�WDUJHW�ZH�KROG�WKH�VROHQRLG

RQ�IRU�[�VHFRQGV�EHIRUH�WXUQLQJ�LW�RII��,W�LV�FDOOHG�D�72)��WLPHU�RII�GHOD\��DQG�LV�OHVV

FRPPRQ�WKDQ�WKH�RQ�GHOD\�W\SH�OLVWHG�DERYH���L�H��IHZ�PDQXIDFWXUHUV�LQFOXGH�WKLV�W\SH

RI�WLPHU��

5HWHQWLYH�RU�$FFXPXODWLQJ�WLPHU��7KLV�W\SH�RI�WLPHU�QHHGV���LQSXWV��2QH�LQSXW�VWDUWV

WKH�WLPLQJ�HYHQW��L�H��WKH�FORFN�VWDUWV�WLFNLQJ��DQG�WKH�RWKHU�UHVHWV�LW��7KH�RQ�RII�GHOD\

WLPHUV�DERYH�ZRXOG�EH� UHVHW� LI� WKH� LQSXW� VHQVRU�ZDVQW�RQ�RII� IRU� WKH�FRPSOHWH� WLPHU

GXUDWLRQ��7KLV�WLPHU�KRZHYHU�KROGV�RU�UHWDLQV�WKH�FXUUHQW�HODSVHG�WLPH�ZKHQ�WKH�VHQVRU

WXUQV�RII� LQ�PLG�VWUHDP��)RU�H[DPSOH��ZH�ZDQW� WR�NQRZ�KRZ�ORQJ�D�VHQVRU� LV�RQ�IRU

GXULQJ�D���KRXU�SHULRG��,I�ZH�XVH�RQH�RI�WKH�DERYH�WLPHUV�WKH\�ZLOO�NHHS�UHVHWWLQJ�ZKHQ

WKH�VHQVRU�WXUQV�RII�RQ��7KLV�WLPHU�KRZHYHU��ZLOO�JLYH�XV�D�WRWDO�RU�DFFXPXODWHG�WLPH��,W

LV�RIWHQ�FDOOHG�DQ�572��UHWHQWLYH�WLPHU��RU�705$��DFFXPXODWLQJ�WLPHU��

/HWV�QRZ�VHH�KRZ�WR�XVH�WKHP��:H�W\SLFDOO\�QHHG�WR�NQRZ���WKLQJV�

��:KDW�ZLOO�HQDEOH�WKH�WLPHU��7\SLFDOO\�WKLV�LV�RQH�RI�WKH�LQSXWV���D�VHQVRU�FRQQHFWHG�WR

LQSXW������IRU�H[DPSOH��

��+RZ�ORQJ�ZH�ZDQW�WR�GHOD\�EHIRUH�ZH�UHDFW��/HWV�ZDLW���VHFRQGV�EHIRUH�ZH�WXUQ�RQ�D

VROHQRLG��IRU�H[DPSOH�

:KHQ�WKH�LQVWUXFWLRQV�EHIRUH�WKH�WLPHU�V\PERO�DUH�WUXH�WKH�WLPHU�VWDUWV��WLFNLQJ���:KHQ

WKH�WLPH�HODSVHV�WKH�WLPHU�ZLOO�DXWRPDWLFDOO\�FORVH�LWV�FRQWDFWV��:KHQ�WKH�SURJUDP�LV

UXQQLQJ�RQ� WKH�SOF� WKH�SURJUDP�W\SLFDOO\�GLVSOD\V� WKH�HODSVHG�RU� �DFFXPXODWHG�� WLPH

IRU�XV�VR�ZH�FDQ�VHH�WKH�FXUUHQW�YDOXH��7\SLFDOO\�WLPHUV�FDQ�WLFN�IURP���WR������RU���WR

������ WLPHV�� :K\� WKH� ZHLUG� QXPEHUV"� $JDLQ� LWV� EHFDXVH� PRVW� SOFV� KDYH� ���ELW

WLPHUV��:HOO�JHW�LQWR�ZKDW�WKLV�PHDQV�LQ�D� ODWHU�FKDSWHU�EXW�IRU�QRZ�VXIILFH�LW� WR�VD\

WKDW��������LV����ELW�%&'��ELQDU\�FRGHG�GHFLPDO��DQG�WKDW���WR�������LV����ELW�ELQDU\�

Page 26: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

(DFK� WLFN� RI� WKH� FORFN� LV� HTXDO� WR� [�VHFRQGV�� 7\SLFDOO\� HDFK� PDQXIDFWXUHU� RIIHUV

VHYHUDO�GLIIHUHQW� WLFNV��0RVW�PDQXIDFWXUHUV�RIIHU����DQG�����PV� LQFUHPHQWV� �WLFNV�RI

WKH�FORFN���$Q��PV��LV�D�PLOOL�VHFRQG�RU�������WK�RI�D�VHFRQG��6HYHUDO�PDQXIDFWXUHUV

DOVR�RIIHU��PV�DV�ZHOO�DV���VHFRQG�LQFUHPHQWV��7KHVH�GLIIHUHQW�LQFUHPHQW�WLPHUV�ZRUN

WKH�VDPH�DV�DERYH�EXW�VRPHWLPHV� WKH\�KDYH�GLIIHUHQW�QDPHV� WR� VKRZ� WKHLU� WLPHEDVH�

6RPH� DUH� 70+� �KLJK� VSHHG� WLPHU��� 706� �VXSHU� KLJK� VSHHG� WLPHU�� RU� 705$)

�DFFXPXODWLQJ�IDVW�WLPHU��

+HUH� LV� D� W\SLFDO� WLPHU� LQVWUXFWLRQ� V\PERO� ZH� ZLOO� HQFRXQWHU� �GHSHQGLQJ� RQ� ZKLFK

PDQXIDFWXUHU� ZH� FKRRVH�� DQG� KRZ� WR� XVH� LW�� 5HPHPEHU� WKDW� ZKLOH� WKH\� PD\� ORRN

GLIIHUHQW� WKH\�DUH�DOO�XVHG�EDVLFDOO\� WKH�VDPH�ZD\�� ,I�ZH�FDQ�VHWXS�RQH�ZH�FDQ�VHWXS

DQ\�RI�WKHP�

7KLV� WLPHU� LV� WKH�RQ�GHOD\�W\SH�DQG�LV�QDPHG�7[[[��:KHQ�WKH�HQDEOH� LQSXW� LV�RQ� WKH

WLPHU� VWDUWV� WR� WLFN��:KHQ� LW� WLFNV� \\\\\� �WKH� SUHVHW� YDOXH�� WLPHV�� LW�ZLOO� WXUQ� RQ� LWV

FRQWDFWV� WKDW�ZH�ZLOO�XVH� ODWHU� LQ� WKH�SURJUDP��5HPHPEHU� WKDW� WKH�GXUDWLRQ�RI�D� WLFN

�LQFUHPHQW��YDULHV�ZLWK�WKH�YHQGRU�DQG�WKH�WLPHEDVH�XVHG���L�H��D�WLFN�PLJKW�EH��PV�RU

��VHFRQG�RU�����

+HUHV�WKH�V\PERO�VKRZQ�RQ�D�ODGGHU�GLDJUDP�

,Q�WKLV�GLDJUDP�ZH�ZDLW�IRU�LQSXW������WR�WXUQ�RQ��:KHQ�LW�GRHV�WLPHU�7�����D����PV

LQFUHPHQW�WLPHU��VWDUWV�WLFNLQJ��,W�ZLOO�WLFN�����WLPHV��(DFK�WLFN��LQFUHPHQW��LV����PV

VR�WKH�WLPHU�ZLOO�EH�D������PV��L�H�����VHFRQG��WLPHU�����WLFNV�;����PV� �������PV�

:KHQ����VHFRQGV�KDYH�HODSVHG��WKH�7����FRQWDFWV�FORVH�DQG�����WXUQV�RQ��:KHQ�LQSXW

�����WXUQV�RII��IDOVH��WKH�WLPHU�7����ZLOO�UHVHW�EDFN�WR���FDXVLQJ�LWV�FRQWDFWV� WR� WXUQ

RII� �EHFRPH� IDOVH�� WKHUHE\�PDNLQJ�RXWSXW����� WXUQ�EDFN�RII��$Q�DFFXPXODWLQJ� WLPHU

ZRXOG�ORRN�VLPLODU�WR�WKLV�

Page 27: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

7KLV�WLPHU�LV�QDPHG�7[[[��:KHQ�WKH�HQDEOH�LQSXW�LV�RQ�WKH�WLPHU�VWDUWV�WR�WLFN��:KHQ�LW

WLFNV�\\\\\��WKH�SUHVHW�YDOXH��WLPHV��LW�ZLOO�WXUQ�RQ�LWV�FRQWDFWV�WKDW�ZH�ZLOO�XVH�ODWHU�LQ

WKH�SURJUDP��5HPHPEHU�WKDW�WKH�GXUDWLRQ�RI�D�WLFN��LQFUHPHQW��YDULHV�ZLWK�WKH�YHQGRU

DQG� WKH� WLPHEDVH� XVHG�� �L�H�� D� WLFN�PLJKW� EH� �PV� RU� �� VHFRQG� RU������ ,I� KRZHYHU�� WKH

HQDEOH� LQSXW� WXUQV� RII� EHIRUH� WKH� WLPHU� KDV� FRPSOHWHG�� WKH� FXUUHQW� YDOXH� ZLOO� EH

UHWDLQHG��:KHQ�WKH�LQSXW�WXUQV�EDFN�RQ��WKH�WLPHU�ZLOO�FRQWLQXH�IURP�ZKHUH�LW�OHIW�RII�

7KH�RQO\�ZD\�WR�IRUFH�WKH�WLPHU�WR�EDFN�EDFN�WR�LWV�SUHVHW�YDOXH�WR�VWDUW�DJDLQ�LV�WR�WXUQ

RQ�WKH�UHVHW�LQSXW�

+HUHV�WKH�V\PERO�LQ�D�ODGGHU�GLDJUDP�

,Q�WKLV�GLDJUDP�ZH�ZDLW�IRU�LQSXW������WR�WXUQ�RQ��:KHQ�LW�GRHV�WLPHU�7�����D���PV

LQFUHPHQW�WLPHU��VWDUWV�WLFNLQJ��,W�ZLOO�WLFN�����WLPHV��(DFK�WLFN��LQFUHPHQW��LV���PV�VR

WKH�WLPHU�ZLOO�EH�D�����PV��L�H����VHFRQG��WLPHU�����WLFNV�;���PV� ������PV��:KHQ��

VHFRQG�KDV�HODSVHG��WKH�7����FRQWDFWV�FORVH�DQG�����WXUQV�RQ��,I�LQSXW������WXUQV�EDFN

RII�WKH�FXUUHQW�HODSVHG�WLPH�ZLOO�EH�UHWDLQHG��:KHQ������WXUQV�EDFN�RQ�WKH�WLPHU�ZLOO

FRQWLQXH�ZKHUH�LW�OHIW�RII��:KHQ�LQSXW������WXUQV�RQ��WUXH�� WKH�WLPHU�7����ZLOO�UHVHW

EDFN� WR���FDXVLQJ� LWV� FRQWDFWV� WR� WXUQ�RII� �EHFRPH� IDOVH�� WKHUHE\�PDNLQJ�RXWSXW����

WXUQ�EDFN�RII�

2QH�LPSRUWDQW�WKLQJ�WR�QRWH�LV�WKDW�FRXQWHUV�DQG�WLPHUV�FDQW�KDYH�WKH�VDPH�QDPH��LQ

PRVW�SOFV���7KLV�LV�EHFDXVH�WKH\�W\SLFDOO\�XVH�WKH�VDPH�UHJLVWHUV�

$OZD\V� UHPHPEHU� WKDW�DOWKRXJK� WKH� V\PEROV�PD\� ORRN�GLIIHUHQW� WKH\� DOO� RSHUDWH� WKH

VDPH�ZD\��7\SLFDOO\�WKH�PDMRU�GLIIHUHQFHV�DUH�LQ�WKH�GXUDWLRQ�RI�WKH�WLFNV��LQFUHPHQWV��

7LPHU�$FFXUDF\KWWS���ZZZ�SOFV�QHW�WLPHDFF���KWP

:HOO��QRZ� WKDW�ZHYH� VHHQ�KRZ� WLPHUV�DUH�FUHDWHG�DQG�XVHG�� OHWV� OHDUQ�D� OLWWOH�DERXW

WKHLU�SUHFLVLRQ��:KHQ�ZH�DUH�FUHDWLQJ�D�WLPHU�WKDW�ODVWV�D�IHZ�VHFRQGV��RU�PRUH��ZH�FDQ

Page 28: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

W\SLFDOO\�QRW�EH�YHU\�FRQFHUQHG�DERXW�WKHLU�SUHFLVLRQ�EHFDXVH�LWV�XVXDOO\�LQVLJQLILFDQW�

+RZHYHU��ZKHQ�ZHUH�FUHDWLQJ�WLPHUV� WKDW�KDYH�D�GXUDWLRQ� LQ� WKH�PLOOLVHFRQG���PV�

�������VHFRQG��UDQJH�ZH�0867�EH�FRQFHUQHG�DERXW�WKHLU�SUHFLVLRQ�

7KHUH�DUH�JHQHUDO�WZR�W\SHV�RI�HUURUV�ZKHQ�XVLQJ�D�WLPHU��7KH�ILUVW�LV�FDOOHG�DQ�LQSXW

HUURU��7KH�RWKHU�LV�FDOOHG�DQ�RXWSXW�HUURU��7KH�WRWDO�HUURU�LV�WKH�VXP�RI�ERWK�WKH�LQSXW

DQG�RXWSXW�HUURUV�

,QSXW�HUURU��$Q�HUURU�RFFXUV�GHSHQGLQJ�XSRQ�ZKHQ�WKH�WLPHU�LQSXW�WXUQV�RQ�GXULQJ�WKH

VFDQ�F\FOH��:KHQ�WKH�LQSXW�WXUQV�RQ�LPPHGLDWHO\�DIWHU�WKH�SOF�ORRNV�DW�WKH�VWDWXV�RI�WKH

LQSXWV�GXULQJ�WKH�VFDQ�F\FOH��WKH�LQSXW�HUURU�ZLOO�EH�DW�LWV�ODUJHVW���L�H��PRUH�WKDQ���IXOO

VFDQ�WLPH����7KLV�LV�EHFDXVH��DV�\RX�ZLOO�UHFDOO���VHH�VFDQ�WLPH�FKDSWHU��WKH�LQSXWV�DUH

ORRNHG�DW�RQFH�RQFH�GXULQJ�D�VFDQ�� ,I� LW�ZDVQW�RQ�ZKHQ� WKH�SOF� ORRNHG�DQG� WXUQV�RQ

ODWHU� LQ� WKH�VFDQ�ZH�REYLRXVO\�KDYH�DQ�HUURU��)XUWKHU�ZH�KDYH�WR�ZDLW�XQWLO� WKH� WLPHU

LQVWUXFWLRQ� LV� H[HFXWHG� GXULQJ� WKH� SURJUDP� H[HFXWLRQ� SDUW� RI� WKH� VFDQ�� ,I� WKH� WLPHU

LQVWUXFWLRQ�LV�WKH�ODVW�LQVWUXFWLRQ�RQ�WKH�UXQJ�LW�FRXOG�EH�TXLWH�D�ELJ�HUURU�

2XWSXW� HUURU��$Q�DQRWKHU� HUURU�RFFXUV�GHSHQGLQJ�XSRQ�ZKHQ� LQ� WKH� ODGGHU� WKH� WLPHU

DFWXDOO\��WLPHV�RXW���H[SLUHV��DQG�ZKHQ�WKH�SOF�ILQLVKHV�H[HFXWLQJ�WKH�SURJUDP�WR�JHW

WR�WKH�SDUW�RI�WKH�VFDQ�ZKHQ�LW�XSGDWHV�WKH�RXWSXWV���DJDLQ��VHH�VFDQ�WLPH�FKDSWHU��7KLV

LV�EHFDXVH�WKH�WLPHU�ILQLVKHV�GXULQJ�WKH�SURJUDP�H[HFXWLRQ�EXW�WKH�SOF�PXVW�ILUVW�ILQLVK

H[HFXWLQJ�WKH�UHPDLQGHU�RI�WKH�SURJUDP�EHIRUH�LW�FDQ�WXUQ�RQ�WKH�DSSURSULDWH�RXWSXW�

+HUHV�D�GLDJUDP�LOOXVWUDWLQJ�WKH�ZRUVW�SRVVLEOH�LQSXW�HUURU��<RX�ZLOO�QRWH�IURP�LW�WKDW

WKH�ZRUVW�SRVVLEOH�LQSXW�HUURU�ZRXOG�EH���FRPSOHWH�VFDQ�WLPH�����SURJUDP�H[HFXWLRQ

WLPH�� 5HPHPEHU� WKDW� D� SURJUDP� H[HFXWLRQ� WLPH� YDULHV� IURP� SURJUDP� WR� SURJUDP�

�GHSHQGV�KRZ�PDQ\�LQVWUXFWLRQV�DUH�LQ�WKH�SURJUDP��

1RZ�KHUHV�D�GLDJUDP�LOOXVWUDWLQJ�WKH�ZRUVW�SRVVLEOH�RXWSXW�HUURU��<RX�FDQ�VHH�IURP�LW

WKDW�WKH�ZRUVW�SRVVLEOH�RXWSXW�HUURU�ZRXOG�EH���FRPSOHWH�VFDQ�WLPH�

Page 29: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

%DVHG�XSRQ�WKH�DERYH�LQIRUPDWLRQ�ZH�FDQ�QRZ�VHH�WKDW�WKH�WRWDO�ZRUVW�SRVVLEOH�WLPHU

HUURU�ZRXOG�EH�HTXDO�WR���VFDQ�WLPH�����SURJUDP�H[HFXWLRQ�WLPH�����VFDQ�WLPH� ���VFDQ

WLPHV�����SURJUDP�H[HFXWLRQ�WLPH�

:KDW�GRHV�WKLV�UHDOO\�PHDQ"�,W�PHDQV�WKDW�HYHQ�WKRXJK�PRVW�PDQXIDFWXUHUV�FXUUHQWO\

KDYH�WLPHUV�ZLWK��PV�LQFUHPHQWV�WKH\�UHDOO\�VKRXOGQW�EH�XVHG�IRU�GXUDWLRQV�OHVV�WKDQ�D

IHZ�PLOOLVHFRQGV��7KLV�DVVXPHV�WKDW�\RXU�VFDQ�WLPH�LV��PV��,I�\RXU�VFDQ�WLPH�LV��PV

\RX� KDG� EHWWHU� QRW� XVH� D� WLPHU� ZLWK� D� GXUDWLRQ� OHVV� WKDQ� DERXW� ��PV�� 7KH� SRLQW� LV

KRZHYHU��MXVW�VR�WKDW�ZH�ZLOO�NQRZ�ZKDW�HUURUV�ZH�FDQ�H[SHFW��,I�ZH�NQRZ�ZKDW�HUURU

WR�H[SHFW��ZH�FDQ�WKHQ�WKLQN�DERXW�ZKHWKHU�WKLV�DPRXQW�RI�HUURU�LV�DFFHSWDEOH�IRU�RXU

DSSOLFDWLRQ��,Q�PRVW�DSSOLFDWLRQV�WKLV�HUURU� LV� LQVLJQLILFDQW�EXW� LQ�VRPH�KLJK�VSHHG�RU

YHU\�SUHFLVH�DSSOLFDWLRQV�WKLV�HUURU�FDQ�EH�9(5<�VLJQLILFDQW�

:H�VKRXOG�DOVR�QRWH�WKDW�WKH�DERYH�HUURUV�DUH�RQO\�WKH��VRIWZDUH�HUURUV���7KHUH�LV�DOVR

D�KDUGZDUH�LQSXW�HUURU�DV�ZHOO�DV�D�KDUGZDUH�RXWSXW�HUURU��7KH�KDUGZDUH�LQSXW�HUURU�LV

FDXVHG�E\�WKH�WLPH�LW� WDNHV�IRU� WKH�SOF� WR�DFWXDOO\�UHDOL]H� WKDW� WKH�LQSXW� LV�RQ�ZKHQ�LW

VFDQV� LWV� LQSXWV�� 7\SLFDOO\� WKLV� GXUDWLRQ� LV� DERXW� ��PV�� 7KLV� LV� EHFDXVH� PDQ\� SOFV

UHTXLUH�WKDW�DQ�LQSXW�VKRXOG�EH�SK\VLFDOO\�RQ�IRU�D�IHZ�VFDQV�EHIRUH�LW�GHWHUPLQHV�LWV

SK\VLFDOO\�RQ���WR�HOLPLQDWH�QRLVH�RU��ERXQFLQJ��LQSXWV��7KH�KDUGZDUH�RXWSXW�HUURU�LV

FDXVHG�E\�WKH�WLPH�LW�WDNHV�IURP�ZKHQ�WKH�SOF�WHOOV�LWV�RXWSXW�WR�SK\VLFDOO\�WXUQ�RQ�XQWLO

WKH� PRPHQW� LW� DFWXDOO\� GRHV�� 7\SLFDOO\� D� WUDQVLVWRU� WDNHV� DERXW� ���PV� ZKHUHDV� D

PHFKDQLFDO�UHOD\�WDNHV�DERXW���PV��7KH�HUURU�NHHSV�RQ�JURZLQJ�GRHVQW�LW��

2QH�VKRWVKWWS���ZZZ�SOFV�QHW�RQHVKRW���KWP

/HWV� QRZ�GLVFXVV� DQ� LQWHUHVWLQJ� DQG� LQYDOXDEOH� SURJUDPPLQJ� WRRO��$W� ILUVW� JODQFH� LW

PLJKW�EH�GLIILFXOW�WR�ILJXUH�RXW�ZK\�VXFK�DQ�LQVWUXFWLRQ�LV�QHHGHG��$IWHU�ZH�XQGHUVWDQG

ZKDW�WKLV�LQVWUXFWLRQ�GRHV�DQG�KRZ�WR�XVH�LW��KRZHYHU��WKH�QHFHVVLW\�ZLOO�EHFRPH�FOHDU�

$�RQH�VKRW�LV�XVHG�WR�PDNH�VRPHWKLQJ�KDSSHQ�IRU�21/<���6&$1���\RX�GR�UHPHPEHU

ZKDW�D�VFDQ�LV��ULJKW""��0RVW�PDQXIDFWXUHUV�KDYH�RQH�VKRWV�WKDW�UHDFW�WR�DQ�RII� WR�RQ

WUDQVLWLRQ�DQG�D�GLIIHUHQW�W\SH�WKDW�UHDFWV�WR�DQ�RQ�WR�RII�WUDQVLWLRQ��6RPH�QDPHV�IRU�WKH

LQVWUXFWLRQV� FRXOG� EH� GLIX�GLIG� �GLIIHUHQWLDWH� XS�GRZQ��� VRWX�VRWG� �VLQJOH� RXWSXW

XS�GRZQ���RVU��RQH�VKRW�ULVLQJ��DQG�RWKHUV��7KH\�DOO��KRZHYHU��HQG�XS�ZLWK� WKH�VDPH

UHVXOW�UHJDUGOHVV�RI�WKH�QDPH�

+HUHV�WKH�V\PERO�IRU�D�GLIX�LQVWUXFWLRQ

$�GLIG�ORRNV�WKH�VDPH�EXW�LQVLGH�WKH�V\PERO�LW�VD\V��GLIG���6RPH�RI�WKH�PDQXIDFWXUHUV

KDYH�LW�LQ�WKH�VKDSH�RI�D�ER[�EXW��UHJDUGOHVV�RI�WKH�V\PERO��WKH\�DOO�IXQFWLRQ�WKH�VDPH

ZD\��)RU� WKRVH�PDQXIDFWXUHUV� WKDW�GRQW� LQFOXGH�D�GLIIHUHQWLDWH�GRZQ�LQVWUXFWLRQ��\RX

Page 30: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

FDQ�JHW�WKH�VDPH�HIIHFW�E\�SXWWLQJ�D�1&��QRUPDOO\�FORVHG��LQVWUXFWLRQ�EHIRUH�LW�LQVWHDG

RI�D�12��QRUPDOO\�RSHQ��LQVWUXFWLRQ���L�H��UHYHUVH�WKH�ORJLF�EHIRUH�WKH�GLIX�LQVWUXFWLRQ�

/HWV� QRZ� VHWXS� DQ� DSSOLFDWLRQ� WR� VHH� KRZ� WKLV� LQVWUXFWLRQ� DFWXDOO\� IXQFWLRQV� LQ� D

ODGGHU�� 7KLV� LQVWUXFWLRQ� LV� PRVW� RIWHQ� XVHG� ZLWK� VRPH� RI� WKH� DGYDQFHG� LQVWUXFWLRQV

ZKHUH�ZH�GR�VRPH� WKLQJV� WKDW�0867�KDSSHQ�RQO\�RQFH��+RZHYHU�� VLQFH�ZH�KDYHQW

JRWWHQ� WKDW� IDU� \HW�� OHWV� VHW� XS� D� IOLS�IORS� FLUFXLW�� ,Q� VLPSOH� WHUPV�� D� IOLS�IORS� WXUQV

VRPHWKLQJ� DURXQG� HDFK� WLPH� DQ� DFWLRQ� KDSSHQV�� +HUH� ZHOO� XVH� D� VLQJOH� SXVKEXWWRQ

VZLWFK�� 7KH� ILUVW� WLPH� WKH� RSHUDWRU� SXVKHV� LW� ZH� ZDQW� DQ� RXWSXW� WR� WXUQ� RQ�� ,W� ZLOO

UHPDLQ��ODWFKHG��RQ�XQWLO�WKH�QH[W�WLPH�WKH�RSHUDWRU�SXVKHV�WKH�EXWWRQ��:KHQ�KH�GRHV�

WKH�RXWSXW�WXUQV�RII�

+HUHV�WKH�ODGGHU�GLDJUDP�WKDW�GRHV�MXVW�WKDW�

1RZ�WKLV�ORRNV�FRQIXVLQJ���$FWXDOO\�LWV�QRW�LI�ZH�WDNH�LW�RQH�VWHS�DW�D�WLPH�

5XQJ���:KHQ�12��QRUPDOO\�RSHQ��LQSXW������EHFRPHV�WUXH�',)8������EHFRPHV�WUXH�

5XQJ����12������ LV� WUXH��12������ UHPDLQV� IDOVH��1&������ UHPDLQV� WUXH��1&�����

WXUQV� IDOVH��6LQFH�ZH�KDYH� D� WUXH�SDWK�� �12�������1&�������287������ EHFRPHV

WUXH�

5XQJ����12������LV�WUXH�WKHUHIRUH�287�����WXUQV�WUXH�

1H[W�6FDQ

5XQJ����12������UHPDLQV� WUXH��',)8������QRZ�EHFRPHV�IDOVH��7KLV� LV�EHFDXVH� WKH

',)8�LQVWUXFWLRQ�LV�RQO\�WUXH�IRU�RQH�VFDQ���L�H��WKH�ULVLQJ�HGJH�RI�WKH�ORJLF�EHIRUH�LW�RQ

WKH�UXQJ�

5XQJ����12������LV�IDOVH��12������UHPDLQV� WUXH��1&������ LV� IDOVH��1&������ WXUQV

WUXH��6LQFH�ZH�67,//�KDYH� D� WUXH�SDWK�� �12�������1&�������287������ UHPDLQV

WUXH�

5XQJ����12������LV�WUXH�WKHUHIRUH�287�����UHPDLQV�WUXH�

$IWHU�����VFDQV��12������ WXUQV�RII� �EHFRPHV� IDOVH���7KH� ORJLF� UHPDLQV� LQ� WKH� VDPH

VWDWH�DV��QH[W�VFDQ��VKRZQ�DERYH���GLIX�GRHVQW�UHDFW�WKHUHIRUH�WKH�ORJLF�VWD\V�WKH�VDPH

RQ�UXQJV���DQG���

Page 31: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

2Q�VFDQ�����12������WXUQV�EDFN�RQ���EHFRPHV�WUXH�

5XQJ���:KHQ�12��QRUPDOO\�RSHQ��LQSXW������EHFRPHV�WUXH�',)8������EHFRPHV�WUXH�

5XQJ����12������LV�WUXH��12������UHPDLQV�WUXHH��1&������EHFRPHV�IDOVH��1&�����

DOVR�EHFRPHV�IDOVH��6LQFH�ZH�QR�ORQJHU�KDYH�D�WUXH�SDWK��287������EHFRPHV�IDOVH�

5XQJ����12������LV�IDOVH�WKHUHIRUH�287�����EHFRPHV�IDOVH�

([HFXWLQJ� WKH� SURJUDP� �� LQVWUXFWLRQ� DW� D� WLPH�PDNHV� WKLV� DQG� DQ\� SURJUDP� HDV\� WR

IROORZ��$FWXDOO\�D�ODUJHU�SURJUDP�WKDW�MXPSV�DURXQG�PLJKW�EH�GLIILFXOW�WR�IROORZ�EXW�D

SHQFLO�GUDZLQJ�RI�WKH�UHJLVWHUV�VXUH�GRHV�KHOS���

0DVWHU�&RQWUROVKWWS���ZZZ�SOFV�QHW�PDVWHU���KWP

/HWV�QRZ�ORRN�DW�ZKDW�DUH�FDOOHG�PDVWHU�FRQWUROV��0DVWHU�FRQWUROV�FDQ�EH�WKRXJKW�RI�DV

�HPHUJHQF\�VWRS�VZLWFKHV���$Q�HPHUJHQF\�VWRS�VZLWFK�W\SLFDOO\�LV�D�ELJ�UHG�EXWWRQ�RQ

D�PDFKLQH�WKDW�ZLOO�VKXW�LW�RII�LQ�FDVHV�RI�HPHUJHQF\��1H[W�WLPH�\RXUH�DW�WKH�ORFDO�JDV

VWDWLRQ� VWDWLRQ� ORRN� QHDU� WKH� GRRU� RQ� WKH� RXWVLGH� WR� VHH� DQ� H[DPSOH� RI� DQ� H�

VWRS� ,03257$17��,P�QRW� LPSO\LQJ�WKDW� WKLV� LQVWUXFWLRQ�LV�D�VXEVWLWXWH�IRU�D��KDUG

ZLUHG��H�VWRS�VZLWFK��7KHUH�LV�QR�VXEVWLWXWH�IRU�VXFK�D�VZLWFK����5DWKHU�LWV�MXVW�DQ�HDV\

ZD\�WR�JHW�WR�XQGHUVWDQG�WKHP�

7KH�PDVWHU� FRQWURO� LQVWUXFWLRQ� W\SLFDOO\� LV� XVHG� LQ� SDLUV�ZLWK� D�PDVWHU� FRQWURO� UHVHW�

+RZHYHU� WKLV�YDULHV�E\�PDQXIDFWXUHU��6RPH�XVH�0&5� LQ�SDLUV� LQVWHDG�RI� WHDPLQJ� LW

ZLWK�DQRWKHU�V\PERO��,W�LV�FRPPRQO\�DEEUHYLDWHG�DV�0&�0&5��PDVWHU�FRQWURO�PDVWHU

FRQWURO� UHVHW��� 0&6�0&5� �PDVWHU� FRQWURO� VHW�PDVWHU� FRQWURO� UHVHW�� RU� MXVW� VLPSO\

0&5��PDVWHU�FRQWURO�UHVHW��

+HUHV�RQH�H[DPSOH�RI�KRZ�D�PDVWHU�FRQWURO�V\PERO�ORRNV�

ZKHUHDV�WKLV�LV�DQ�H[DPSOH�RI�D�PDVWHU�FRQWURO�UHVHW�

7R�PDNH�WKLQJV�LQWHUHVWLQJ��PDQ\�PDQXIDFWXUHUV�PDNH�WKHP�DFW�GLIIHUHQWO\��0RUH�RQ

WKDW�LQ�D�PRPHQW�

/HWV� QRZ� WDNH� D� ORRN� DW� KRZ� LWV� XVHG� LQ� D� ODGGHU� GLDJUDP�� &RQVLGHU� WKH� IROORZLQJ

H[DPSOH�

Page 32: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

+HUHV�KRZ�GLIIHUHQW�SOFV�ZLOO�UXQ�WKLV�SURJUDP�

0DQXIDFWXUHU�;��,Q�WKLV�H[DPSOH��UXQJV���DQG���DUH�RQO\�H[HFXWHG�ZKHQ�LQSXW������LV

RQ��WUXH���,I�LQSXW������LV�QRW�WUXH�WKH�SOF�SUHWHQGV�WKDW�WKH�ORJLF�EHWZHHQ�WKH�PF�DQG

PFU�LQVWUXFWLRQV�GRHV�QRW�H[LVW��,W�ZRXOG�WKHUHIRUH�E\SDVV�WKLV�EORFN�RI�LQVWUXFWLRQV�DQG

LPPHGLDWHO\�JR�WR�WKH�UXQJ�DIWHU�WKH�PFU�LQVWUXFWLRQ�

&RQYHUVHO\��LI�LQSXW������LV�WUXH��WKH�SOF�ZRXOG�H[HFXWH�UXQJV���DQG���DQG�XSGDWH�WKH

VWDWXV� RI� RXWSXWV� ����� DQG� ����� DFFRUGLQJO\�� 6R�� LI� LQSXW� ����� LV� WUXH�� SURJUDP

H[HFXWLRQ�JRHV�WR�UXQJ����,I�LQSXW������LV�WUXH������ZLOO�EH�WUXH�DQG�KHQFH�LW�ZLOO�WXUQ

RQ�ZKHQ�WKH�SOF�XSGDWHV�WKH�RXWSXWV��,I�LQSXW������LV�WUXH��L�H��SK\VLFDOO\�RII�������ZLOO

EH�WUXH�DQG�KHQFH�LW�ZLOO�WXUQ�RQ�ZKHQ�WKH�SOF�XSGDWHV�WKH�RXWSXWV��0&5�MXVW�WHOOV�WKH

SOF��WKDWV�WKH�HQG�RI� WKH�PF�PFU�EORFN���,Q� WKLV�SOF��VFDQ�WLPH�LV�QRW�H[WHQGHG�ZKHQ

WKH� PF�PFU� EORFN� LV� QRW� H[HFXWHG� EHFDXVH� WKH� SOF� SUHWHQGV� WKH� ORJLF� LQ� WKH� EORFN

GRHVQW�H[LVW��,Q�RWKHU�ZRUGV��WKH�LQVWUXFWLRQV�LQVLGH�WKH�EORFN�DUHQW�VHHQ�E\�WKH�SOF�DQG

KHQFH�LW�GRHVQW�H[HFXWH�WKHP��,QWHUHVWLQJ�LGHD�

0DQXIDFWXUHU�<��,Q�WKLV�H[DPSOH��UXQJV���DQG���DUH�DOZD\V�H[HFXWHG�UHJDUGOHVV�RI�WKH

VWDWXV�RI�LQSXW�������,I�LQSXW������LV�QRW�WUXH�WKH�SOF�H[HFXWHV�WKH�0&�LQVWUXFWLRQ���L�H�

0&�EHFRPHV�WUXH��,W�WKHQ�IRUFHV�DOO�WKH�LQSXW�LQVWUXFWLRQV�LQVLGH�WKH�EORFN�WR�EH�RII��,I

LQSXW������ LV� WUXH� WKH�0&� LQVWUXFWLRQ� LV�PDGH� WR�EH� IDOVH��6R�� LI� LQSXW������ LV� WUXH�

SURJUDP�H[HFXWLRQ�JRHV�WR�UXQJ����,I�LQSXW������LV�WUXH������ZLOO�EH�WUXH�DQG�KHQFH�LW

ZLOO�WXUQ�RQ�ZKHQ�WKH�SOF�XSGDWHV�WKH�RXWSXWV��,I�LQSXW������LV�WUXH��L�H��SK\VLFDOO\�RII�

�����ZLOO�EH�WUXH�DQG�KHQFH�LW�ZLOO�WXUQ�RQ�ZKHQ�WKH�SOF�XSGDWHV�WKH�RXWSXWV��0&5�MXVW

WHOOV� WKH� SOF� �WKDWV� WKH� HQG� RI� WKH�PF�PFU� EORFN���:KHQ� LQSXW� ����� LV� IDOVH�� LQSXWV

����� DQG� ����� DUH� IRUFHG� RII� UHJDUGOHVV� LI� WKH\UH� SK\VLFDOO\� RQ� RU� RII�� 7KHUHIRUH�

RXWSXWV������DQG������ZLOO�EH�IDOVH�

7KH�GLIIHUHQFH�EHWZHHQ�PDQXIDFWXUHUV�;�DQG�<�DERYH�LV�WKDW�LQ�WKH�<�VFKHPH�WKH�VFDQ

WLPH�ZLOO�EH�WKH�VDPH��ZHOO�FORVH�WR�WKH�VDPH��UHJDUGOHVV�LI�WKH�EORFN�LV�RQ�RU�RII��7KLV

LV�EHFDXVH�WKH�SOF�VHHV�HDFK�LQVWUXFWLRQ�ZKHWKHU�WKH�EORFN�LV�RQ�RU�RII�

0RVW�DOO�PDQXIDFWXUHUV�ZLOO�PDNH�D�SUHYLRXVO\�ODWFKHG�LQVWUXFWLRQ��RQH�WKDWV�LQVLGH�WKH

PF�PFU�EORFN��UHWDLQ�LWV�SUHYLRXV�FRQGLWLRQ��,I�LW�ZDV�WUXH�EHIRUH�LW�ZLOO�UHPDLQ�WUXH��,I

LW�ZDV�IDOVH�EHIRUH�LW�ZLOO�UHPDLQ�IDOVH��7LPHUV�VKRXOG�QRW�EH�XVHG�LQVLGH�WKH�PF�PFU

EORFN� EHFDXVH� VRPH�PDQXIDFWXUHUV� ZLOO� UHVHW� WKHP� WR� ]HUR� ZKHQ� WKH� EORFN� LV� IDOVH

Page 33: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

ZKHUHDV� RWKHU�PDQXIDFWXUHUV� ZLOO� KDYH� WKHP� UHWDLQ� WKH� FXUUHQW� WLPH� VWDWH�� &RXQWHUV

W\SLFDOO\�UHWDLQ�WKHLU�FXUUHQW�FRXQWHG�YDOXH�

+HUHV� WKH� SDUW� WR� QRWH�PRVW� RI� DOO��:KHQ� WKH�PF�PFU� EORFN� LV� RII�� �L�H�� LQSXW� ����

ZRXOG�EH�IDOVH�LQ�WKH�ODGGHU�DERYH��DQ�287%��2XW%DU�RU�2XW1RW��

�LQVWUXFWLRQ�ZRXOG�QRW�EH�SK\VLFDOO\�RQ��,W�LV�IRUFHG�SK\VLFDOO\�RII�

,Q�VXPPDU\��%(�&$5()8/����0RVW�PDQXIDFWXUHUV�XVH�WKH�PDQXIDFWXUHU�<�H[HFXWLRQ

VFKHPH�VKRZQ�DERYH��:KHQ�LQ�GRXEW��KRZHYHU��57)0��L�H��5HDG�7KH�0DQXDO��

6KLIW�5HJLVWHUVKWWS���ZZZ�SOFV�QHW�VKLIW���KWP

,Q�PDQ\�DSSOLFDWLRQV�LW�LV�QHFHVVDU\�WR�VWRUH�WKH�VWDWXV�RI�DQ�HYHQW�WKDW�KDV�SUHYLRXVO\

KDSSHQHG��$V�ZHYH�VHHQ�LQ�SDVW�FKDSWHUV�WKLV�LV�D�VLPSOH�SURFHVV��%XW�ZKDW�GR�ZH�GR

LI�ZH�PXVW�VWRUH�PDQ\�SUHYLRXV�HYHQWV�DQG�DFW�XSRQ�WKHP�ODWHU��$QVZHU��ZH�FDOO�XSRQ

WKH�VKLIW�UHJLVWHU�LQVWUXFWLRQ��:H�XVH�D�UHJLVWHU�RU�JURXS�RI�UHJLVWHUV�WR�IRUP�D�WUDLQ�RI

ELWV��FDUV��WR�VWRUH�WKH�SUHYLRXV�RQ�RII�VWDWXV��(DFK�QHZ�FKDQJH�LQ�VWDWXV�JHWV�VWRUHG�LQ

WKH�ILUVW�ELW�DQG�WKH�UHPDLQLQJ�ELWV�JHW�VKLIWHG�GRZQ�WKH�WUDLQ��+XK"""�5HDG�RQ�

7KH�VKLIW�UHJLVWHU�JRHV�E\�PDQ\�QDPHV��6)7��6KL)7���%6/��%LW�6KLIW�/HIW���6)5��6KLIW

)RUZDUG�5HJLVWHU��DUH�VRPH�RI�WKH�FRPPRQ�QDPHV��7KHVH�UHJLVWHUV�VKLIW�WKH�ELWV�WR�WKH

OHIW��%65��%LW�6KLIW�5LJKW��DQG�6)51��6KLIW�)RUZDUG�5HJLVWHU�1RW��DUH�VRPH�H[DPSOHV

RI� LQVWUXFWLRQV� WKDW� VKLIW�ELWV� WR� WKH� ULJKW��:H� VKRXOG�QRWH� WKDW� QRW� DOO�PDQXIDFWXUHUV

KDYH� VKLIW� UHJLVWHUV� WKDW� VKLIW� GDWD� WR� WKH� ULJKW� EXW� PRVW� DOO� GR� KDYH� OHIW� VKLIWLQJ

UHJLVWHUV�

$�W\SLFDO�VKLIW�UHJLVWHU�LQVWUXFWLRQ�KDV�D�V\PERO�OLNH�WKLV�

1RWLFH� WKDW� WKH� V\PERO� QHHGV� �� LQSXWV� DQG� KDV� VRPH� GDWD� LQVLGH� WKH� V\PERO�� 7KH

UHDVRQV�IRU�HDFK�LQSXW�DUH�DV�IROORZV�

'DWD��7KH�GDWD�LQSXW�JDWKHUV�WKH�WUXH�IDOVH�VWDWXVHV�WKDW�ZLOO�EH�VKLIWHG�GRZQ�WKH�WUDLQ�

:KHQ�WKH�GDWD�LQSXW�LV�WUXH�WKH�ILUVW�ELW��FDU��LQ�WKH�UHJLVWHU��WUDLQ��ZLOO�EH�D����7KLV�GDWD

Page 34: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

LV� RQO\� HQWHUHG� LQWR� WKH� UHJLVWHU� �WUDLQ�� RQ� WKH� ULVLQJ� HGJH� RI� WKH� FORFN� LQSXW�� �VHH

EHORZ�

&ORFN��7KH�FORFN�LQSXW�WHOOV�WKH�VKLIW�UHJLVWHU�WR��GR�LWV� WKLQJ���2Q�WKH�ULVLQJ�HGJH�RI

WKLV� LQSXW�� WKH� VKLIW� UHJLVWHU� VKLIWV� WKH� GDWD� RQH� ORFDWLRQ� RYHU� LQVLGH� WKH� UHJLVWHU� DQG

HQWHUV�WKH�VWDWXV�RI�WKH�GDWD�LQSXW�LQWR�WKH�ILUVW�ELW��2Q�HDFK�ULVLQJ�HGJH�RI�WKLV�LQSXW�WKH

SURFHVV�ZLOO�UHSHDW�

5HVHW��7KH� UHVHW� LQSXW�GRHV� MXVW�ZKDW� LW� VD\V�� ,W� FOHDUV�DOO� WKH�ELWV� LQVLGH� WKH� UHJLVWHU

ZHUH�XVLQJ�WR���

7KH������LQVLGH�WKH�V\PERO�DERYH�LV�WKH�ORFDWLRQ�RI�WKH�ILUVW�ELW�RI�RXU�VKLIW�UHJLVWHU��,I

ZH�WKLQN�RI� WKH�VKLIW�UHJLVWHU�DV�D� WUDLQ��D�FKRR�FKRR�WUDLQ�WKDW� LV�� WKHQ� WKLV�ELW� LV� WKH

ORFRPRWLYH��7KH������LQVLGH�WKH�V\PERO�DERYH�LV�WKH�ODVW�ELW�RI�RXU�VKLIW�UHJLVWHU��,W�LV

WKH� FDERRVH�� 7KHUHIRUH�� ZH� FDQ� VD\� WKDW� ����� DQG� ����� DUH� FDUV� LQ� EHWZHHQ� WKH

ORFRPRWLYH� DQG� WKH� FDERRVH��7KH\� DUH� LQWHUPHGLDWH�ELWV��6R�� WKLV� VKLIW� UHJLVWHU� KDV� �

ELWV���L�H����������������������

/HWV�QRZ�GR�DQ�DSSOLFDWLRQ�WR�VHH�ZK\�KRZ�ZH�FDQ�XVH�WKH�VKLIW�UHJLVWHU��,PDJLQH�DQ

LFH�FUHDP�FRQH�PDFKLQH��:H�KDYH���VWHSV��)LUVW�ZH�YHULI\�WKH�FRQH�LV�QRW�EURNHQ��1H[W

ZH�SXW�LFH�FUHDP�LQVLGH�WKH�FRQH���WXUQ�RQ�RXWSXW������1H[W�ZH�DGG�SHDQXWV���WXUQ�RQ

RXWSXW������$QG�ILQDOO\�ZH�DGG�VSULQNOHV���WXUQ�RQ�RXWSXW������,I� WKH�FRQH�LV�EURNHQ

ZH�REYLRXVO\�GRQW�ZDQW� WR�DGG�LFH�FUHDP�DQG�WKH�RWKHU� LWHPV��7KHUHIRUH�ZH�KDYH�WR

WUDFN�WKH�EDG�FRQH�GRZQ�RXU�SURFHVV� OLQH�VR�WKDW�ZH�FDQ� WHOO� WKH�PDFKLQH�QRW� WR�DGG

HDFK� LWHP��:H�XVH�D�VHQVRU� WR� ORRN�DW� WKH�ERWWRP�RI� WKH�FRQH�� �LQSXW������� ,I� LWV�RQ

WKHQ�WKH�FRQH�LV�SHUIHFW�DQG�LI� LWV�RII� WKHQ�WKH�FRQH� LV�EURNHQ��$Q�HQFRGHU� WUDFNV� WKH

FRQH�JRLQJ�GRZQ�WKH�FRQYH\RU���LQSXW�������$�SXVK�EXWWRQ�RQ�WKH�PDFKLQH�ZLOO�FOHDU

WKH�UHJLVWHU���LQSXW������

+HUHV�ZKDW�WKH�ODGGHU�ZRXOG�ORRN�OLNH�

Page 35: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

/HWV�QRZ�IROORZ�WKH�VKLIW�UHJLVWHU�DV�WKH�RSHUDWLRQ�WDNHV�SODFH��+HUHV�ZKDW� WKH�����

VHULHV�UHJLVWHU��WKH�UHJLVWHU�ZHUH�VKLIWLQJ��ORRNV�OLNH�LQLWLDOO\�

��[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

$�JRRG�FRQH�FRPHV�LQ�IURQW�RI�WKH�VHQVRU��LQSXW��������7KH�VHQVRU��GDWD�LQSXW��WXUQV

RQ�� �����ZLOO� QRW� WXUQ� RQ� WKRXJK� XQWLO� WKH� ULVLQJ� HGJH� RI� WKH� HQFRGHU� �LQSXW� ������

)LQDOO\�WKH�HQFRGHU�QRZ�JHQHUDWHV�D�SXOVH�DQG�WKH�VWDWXV�RI�WKH�GDWD�LQSXW��FRQH�VHQVRU

LQSXW�������LV�WUDQVIHUHG�WR�ELW�������7KH�UHJLVWHU�QRZ�ORRNV�OLNH�

���[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

$V� WKH�FRQYH\LQJ�V\VWHP�PRYHV�RQ��DQRWKHU�FRQH�FRPHV� LQ� IURQW�RI� WKH�VHQVRU��7KLV

WLPH�LWV�D�EURNHQ�FRQH�DQG�WKH�VHQVRU�UHPDLQV�RII��1RZ�WKH�HQFRGHU�JHQHUDWHV�DQRWKHU

SXOVH�� 7KH� ROG� VWDWXV� RI� ELW� ����� LV� WUDQVIHUUHG� WR� ELW� ������ 7KH� ROG� VWDWXV� RI� ����

VKLIWV� WR�������7KH�ROG�VWDWXV�RI������VKLIWV� WR�������$QG�WKH�QHZ�VWDWXV�RI� WKH�GDWD

LQSXW��FRQH�VHQVRU��LV�WUDQVIHUUHG�WR�ELW�������7KH�UHJLVWHU�QRZ�ORRNV�OLNH�

��[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

6LQFH�WKH�UHJLVWHU�VKRZV�WKDW������LV�QRZ�RQ�WKH�ODGGHU�VD\V�WKDW�RXWSXW������ZLOO�WXUQ

RQ�DQG�LFH�FUHDP�LV�SXW�LQ�WKH�FRQH��$V�WKH�FRQYH\LQJ�V\VWHP�FRQWLQXHV�WR�PRYH�RQ�

DQRWKHU�FRQH�FRPHV� LQ� IURQW�RI� WKH� VHQVRU��7KLV� WLPH� LWV� D�JRRG�FRQH�DQG� WKH� VHQVRU

WXUQV� RQ�� 1RZ� WKH� HQFRGHU� JHQHUDWHV� DQRWKHU� SXOVH�� 7KH� ROG� VWDWXV� RI� ELW� ����� LV

WUDQVIHUUHG�WR�ELW�������7KH�ROG�VWDWXV�RI������VKLIWV�WR�������7KH�ROG�VWDWXV�RI�����

VKLIWV�WR�������$QG�WKH�QHZ�VWDWXV�RI�WKH�GDWD�LQSXW��FRQH�VHQVRU��LV�WUDQVIHUUHG�WR�ELW

������7KH�UHJLVWHU�QRZ�ORRNV�OLNH�

��[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

6LQFH�WKH�UHJLVWHU�VKRZV�WKDW������LV�QRZ�RQ�WKH�ODGGHU�VD\V�WKDW�RXWSXW������ZLOO�WXUQ

RQ�DQG�SHDQXWV�DUH�SXW�RQ�WKH�FRQH��6LQFH������QRZ�KROGV�WKH�VWDWXV�RI�D�EURNHQ�FRQH�

����UHPDLQV�RII�LQ�WKH�ODGGHU�DERYH�DQG�QR�LFH�FUHDP�LV�LQVHUWHG�LQWR�WKLV�FRQH��$V�WKH

FRQYH\LQJ�V\VWHP�FRQWLQXHV� WR�PRYH�RQ�� DQRWKHU� FRQH� FRPHV� LQ� IURQW� RI� WKH� VHQVRU�

7KLV� WLPH� LWV� DOVR� D� JRRG� FRQH� DQG� WKH� VHQVRU� WXUQV� RQ��1RZ� WKH� HQFRGHU� JHQHUDWHV

DQRWKHU�SXOVH��7KH�ROG�VWDWXV�RI�ELW������LV� WUDQVIHUUHG�WR�ELW�������7KH�ROG�VWDWXV�RI

Page 36: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

�����VKLIWV�WR�������7KH�ROG�VWDWXV�RI������VKLIWV�WR�������$QG�WKH�QHZ�VWDWXV�RI�WKH

GDWD�LQSXW��FRQH�VHQVRU��LV�WUDQVIHUUHG�WR�ELW�������7KH�UHJLVWHU�QRZ�ORRNV�OLNH�

����[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

6LQFH�WKH�UHJLVWHU�VKRZV�WKDW������LV�QRZ�RQ�WKH�ODGGHU�VD\V�WKDW�RXWSXW������ZLOO�WXUQ

RQ�DQG�VSULQNOHV�DUH�SXW�RQ�WKH�FRQH���,WV�GRQH��\XPP\�����6LQFH������QRZ�KROGV�WKH

VWDWXV�RI�D�EURNHQ�FRQH������UHPDLQV�RII� LQ� WKH� ODGGHU�DERYH�DQG�QR�SHDQXWV�DUH�SXW

RQWR�WKLV�FRQH��6LQFH�WKH�UHJLVWHU�VKRZV�WKDW������LV�QRZ�RQ�WKH�ODGGHU�VD\V�WKDW�RXWSXW

�����ZLOO�WXUQ�RQ�DQG�LFH�FUHDP�LV�SXW�LQ�WKDW�FRQH��$V�WKH�FRQYH\LQJ�V\VWHP�FRQWLQXHV

WR�PRYH� RQ�� DQRWKHU� FRQH� FRPHV� LQ� IURQW� RI� WKH� VHQVRU��7KLV� WLPH� LWV� DQWKHU� EURNHQ

FRQH�DQG�WKH�VHQVRU�WXUQV�RII��1RZ�WKH�HQFRGHU�JHQHUDWHV�DQRWKHU�SXOVH��7KH�ROG�VWDWXV

RI�ELW������LV� WUDQVIHUUHG�WR�ELW�������7KH�ROG�VWDWXV�RI������VKLIWV� WR�������7KH�ROG

VWDWXV�RI������ VKLIWV� WR�������$QG� WKH� QHZ� VWDWXV� RI� WKH� GDWD� LQSXW� �FRQH� VHQVRU�� LV

WUDQVIHUUHG�WR�ELW�������7KH�UHJLVWHU�QRZ�ORRNV�OLNH�

����[[�5HJLVWHU

�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� ��

� � � �

1RWLFH�WKDW�WKH�VWDWXV�RI�RXU�ILUVW�FRQH�KDV�GLVDSSHDUHG��,Q�UHDOLW\�LWV�VLWWLQJ�LQ�ORFDWLRQ

�����EXW�,�GLGQW�ZDQW�WR�GUDZ�DQ�DSSOLFDWLRQ�ZLWK����SURFHVVHV����6XIILFH�LW�WR�VD\�WKDW

DIWHU�WKH�ELW�LV�VKLIWHG�DOO�WKH�ZD\�WR�WKH�OHIW�LW�GLVDSSHDUV�DQG�LV�QHYHU�VHHQ�DJDLQ��,Q

RWKHU� ZRUGV�� LW� KDV� EHHQ� VKLIWHG� RXW� RI� WKH� UHJLVWHU� DQG� LV� HUDVHG� IURP� PHPRU\�

$OWKRXJK�LWV�QRW�GUDZQ�WKH�RSHUDWLRQ�DERYH�ZRXOG�FRQWLQXH�RQ�ZLWK�HDFK�ELW�VKLIWLQJ

RQ�WKH�ULVLQJ�HGJH�RI�WKH�HQFRGHU�VLJQDO�

7KH� VKLIW� UHJLVWHU� LV�PRVW� FRPPRQO\�XVHG� LQ� FRQYH\RU� V\VWHPV�� ODEHOOLQJ�RU�ERWWOLQJ

DSSOLFDWLRQV�� HWF�� 6RPHWLPHV� LWV� DOVR� FRQYHQLHQWO\� XVHG�ZKHQ� WKH� RSHUDWLRQ�PXVW� EH

GHOD\HG�LQ�D�IDVW�PRYLQJ�ERWWOLQJ�OLQH��)RU�H[DPSOH��D�VROHQRLG�FDQW�LPPHGLDWHO\�NLFN

RXW�D�EDG�FDQ�RI�EHHU�ZKHQ� WKH� VHQVRU� VD\V� LWV�EDG��%\� WKH� WLPH� WKH� VROHQRLG�ZRXOG

UHDFW�WKH�FDQ�ZRXOG�KDYH�DOUHDG\�SDVVHG�E\��6R�W\SLFDOO\�WKH�VROHQRLG�LV�ORFDWHG�IXUWKHU

GRZQ�WKH�FRQYH\RU�OLQH�DQG�D�VKLIW�UHJLVWHU�WUDFNV�WKH�FDQ�WR�EH�NLFNHG�RXW�ODWHU�ZKHQ

LWV�PRUH�FRQYHQLHQW�

0RYLQJ�'DWDKWWS���ZZZ�SOFV�QHW�PRYH���KWP

/HWV�QRZ�VWDUW�ZRUNLQJ�ZLWK�VRPH�GDWD��7KLV�LV�ZKDW�ZH�FRQVLGHU�WR�EH�JHWWLQJ�LQWR�WKH

�DGYDQFHG�� IXQFWLRQV� RI� D� SOF�� 7KLV� LV� DOVR� WKH� SRLQW� ZKHUH� ZHOO� VHH� VRPH�PDUNHG

GLIIHUHQFHV�EHWZHHQ�PDQ\�RI�WKH�PDQXIDFWXUHUV�IXQFWLRQDOLW\�DQG�LPSOHPHQWDWLRQ��2Q

WKH�OLQHV�WKDW�IROORZ�ZHOO�H[SORUH�WZR�RI�WKH�PRVW�SRSXODU�ZD\V�WR�JHW�DQG�PDQLSXODWH

GDWD�

Page 37: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

:K\�GR�ZH�ZDQW�WR�JHW�RU�DFTXLUH�GDWD""�7KH�DQVZHU�LV�VLPSOH��/HWV�VD\�WKDW�ZH�DUH

XVLQJ� RQH� RI� WKH�PDQXIDFWXUHUV� RSWLRQDO�PRGXOHV�� 3HUKDSV� LWV� DQ�$�'�PRGXOH�� 7KLV

PRGXOH�DFTXLUHV�$QDORJ�VLJQDOV�IURP�WKH�RXWVLGH�ZRUOG��D�YDU\LQJ�YROWDJH�RU�FXUUHQW�

DQG�FRQYHUWV�WKH�VLJQDO�WR�VRPHWKLQJ�WKH�SOF�FDQ�XQGHUVWDQG��D�GLJLWDO�VLJQDO�L�H���V�DQG

�V��� 0DQXIDFWXUHUV� DXWRPDWLFDOO\� VWRUH� WKLV� GDWD� LQWR� PHPRU\� ORFDWLRQV� IRU� XV�

+RZHYHU��ZH�KDYH�WR�JHW�WKH�GDWD�RXW�RI�WKHUH�DQG�PRYH�LW�VRPH�SODFH�HOVH�RWKHUZLVH

WKH�QH[W�DQDORJ�VDPSOH�ZLOO�UHSODFH�WKH�RQH�ZH�MXVW� WRRN��,Q�RWKHU�ZRUGV��PRYH�LW�RU

ORVH�LW���6RPHWKLQJ�HOVH�ZH�PLJKW�ZDQW�WR�GR�LV�VWRUH�D�FRQVWDQW��L�H��IDQF\�ZRUG�IRU�D

QXPEHU���JHW�VRPH�ELQDU\�GDWD�RII�WKH�LQSXW�WHUPLQDOV���PD\EH�D�WKXPEZKHHO�VZLWFK�LV

FRQQHFWHG� WKHUH�� IRU� H[DPSOH��� GR� VRPH� PDWK� DQG� VWRUH� WKH� UHVXOW� LQ� D� GLIIHUHQW

ORFDWLRQ��HWF���

$V�ZH�VDLG�EHIRUH�WKHUH�DUH�W\SLFDOO\���FRPPRQ�LQVWUXFWLRQ��VHWV��WR�DFFRPSOLVK�WKLV�

6RPH�PDQXIDFWXUHUV�XVH�D�VLQJOH�LQVWUXFWLRQ�WR�GR�WKH�HQWLUH�RSHUDWLRQ�ZKLOH�RWKHUV�XVH

WZR� VHSHUDWH� LQVWUXFWLRQV�� 7KH� WZR� DUH� XVHG� WRJHWKHU� WR� DFFRPSOLVK� WKH� ILQDO� UHVXOW�

/HWV�QRZ�ORRN�EULHIO\�DW�HDFK�LQVWUXFWLRQ�

7KH�VLQJOH�LQVWUXFWLRQ�LV�FRPPRQO\�FDOOHG�029��PRYH���6RPH�YHQGRUV�DOVR�LQFOXGH�D

0291� �PRYH� QRW��� ,W� KDV� WKH� VDPH� IXQFWLRQ� RI� 029� EXW� LW� WUDQVIHUV� WKH� GDWD� LQ

LQYHUWHG�IRUP���L�H��LI�WKH�ELW�ZDV�D����D���LV�VWRUHG�PRYHG�RU�LI�WKH�ELW�ZDV�D����D���LV

VWRUHG�PRYHG���7KH�029�W\SLFDOO\�ORRNV�OLNH�

7KH�SDLUHG�LQVWUXFWLRQ�W\SLFDOO\�LV�FDOOHG�/'$��/RD'�$FFXPXODWRU��DQG�67$��67RUH

$FFXPXODWRU��� 7KH� DFFXPXODWRU� LV� VLPSO\� D� UHJLVWHU� LQVLGH� WKH� &38� ZKHUH� WKH� SOF

VWRUHV�GDWD� WHPSRUDULO\�ZKLOH� LWV�ZRUNLQJ��0RUH� ODWHU��7KH�/'$� LQVWUXFWLRQ� W\SLFDOO\

ORRNV�OLNH

�ZKLOH�WKH�67$�LQVWUXFWLRQ�ORRNV�OLNH�

5HJDUGOHVV�RI�ZKHWKHU�ZH�XVH�WKH�RQH�V\PERO�RU�WZR�V\PERO�LQVWUXFWLRQ�VHW��ZH�KDYH

QR�FKRLFH�DV�LW�GHSHQGV�RQ�ZKRVH�SOF�ZH�XVH��WKH\�ZRUN�WKH�VDPH�ZD\��/HWV�VHH�WKH

VLQJOH�LQVWUXFWLRQ�ILUVW��7KH�029�LQVWUXFWLRQ�QHHGV�WR�NQRZ���WKLQJV�IURP�XV�

VRXUFH��[[[[����7KLV�LV�ZKHUH�WKH�GDWD�ZH�ZDQW�WR�PRYH�LV�ORFDWHG��:H�FRXOG�ZULWH�D

FRQVWDQW� KHUH� ������ IRU� H[DPSOH��� 7KLV�ZRXOG�PHDQ� RXU� VRXUFH� GDWD� LV� WKH� QXPEHU

Page 38: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

������:H�FRXOG�DOVR�ZULWH�D�ORFDWLRQ�RU�DGGUHVV�RI�ZKHUH�WKH�GDWD�ZH�ZDQW�WR�PRYH�LV

ORFDWHG��,I�ZH�ZURWH�'0����WKLV�ZRXOG�PRYH�WKH�GDWD�WKDW�LV�ORFDWHG�LQ�GDWD�PHPRU\

����

GHVWLQDWLRQ��\\\\����7KLV�LV�WKH�ORFDWLRQ�ZKHUH�WKH�GDWD�ZLOO�EH�PRYHG�WR��:H�ZULWH�DQ

DGGUHVV�KHUH��)RU�H[DPSOH�LI�ZH�ZULWH�'0����KHUH�WKH�GDWD�ZRXOG�EH�PRYHG�LQWR�GDWD

PHPRU\������:H�FRXOG�DOVR�ZULWH������KHUH��7KLV�ZRXOG�PHDQ�WKDW�WKH�GDWD�ZRXOG�EH

PRYHG�WR�WKH�SK\VLFDO�RXWSXWV�������ZRXOG�KDYH�WKH�OHDVW�VLJQLILFDQW�ELW�������ZRXOG

KDYH�WKH�QH[W�ELW���������ZRXOG�KDYH�WKH�PRVW�VLJQLILFDQW�ELW��7KLV�ZRXOG�EH�XVHIXO�LI

ZH�KDG�D�ELQDU\�GLVSOD\�FRQQHFWHG�WR�WKH�RXWSXWV�DQG�ZH�ZDQWHG�WR�GLVSOD\�WKH�YDOXH

LQVLGH�D�FRXQWHU�IRU�WKH�PDFKLQH�RSHUDWRU�DW�DOO�WLPHV��IRU�H[DPSOH��

7KH�ODGGHU�GLDJUDP�WR�GR�WKLV�ZRXOG�ORRN�VLPLODU�WR�

1RWLFH�WKDW�ZH�DUH�DOVR�XVLQJ�D�GLIX�LQVWUXFWLRQ�KHUH��7KH�UHDVRQ�LV�VLPSO\�EHFDXVH�LI

ZH�GLGQW� WKH�GDWD�ZRXOG�EH�PRYHG�GXULQJ�HDFK�DQG�HYHU\�VFDQ��6RPHWLPHV� WKLV� LV�D

JRRG�WKLQJ��IRU�H[DPSOH�LI�ZH�DUH�DFTXLULQJ�GDWD�IURP�DQ�$�'�PRGXOH��EXW�RWKHU�WLPHV

LWV�QRW��IRU�H[DPSOH�DQ�H[WHUQDO�GLVSOD\�ZRXOG�EH�XQUHDGDEOH�EHFDXVH�WKH�GDWD�FKDQJHV

WRR�PXFK���7KH�ODGGHU�VKRZV�WKDW�HDFK�WLPH�UHDO�ZRUOG�LQSXW������EHFRPHV�WUXH�GLIX

ZLOO�EHFRPH�WUXH�IRU�RQO\�RQH�VFDQ��$W� WKLV� WLPH�/RD'������ZLOO�EH�WUXH�DQG�WKH�SOF

ZLOO�PRYH�WKH�GDWD�IURP�GDWD�PHPRU\�����DQG�SXW�LW�LQWR�GDWD�PHPRU\������6LPSOH�EXW

HIIHFWLYH�� ,I� LQVWHDG� RI�'0����ZH� KDG�ZULWWHQ� ����� LQ� WKH� V\PERO� ZH�ZRXOG� KDYH

PRYHG��ZULWWHQ��WKH�QXPEHU��FRQVWDQW�������LQWR�'0����

7KH� WZR� V\PERO� LQVWUXFWLRQ� ZRUNV� LQ� WKH� VDPH�PHWKRG� EXW� ORRNV� GLIIHUHQW�� 7R� XVH

WKHP�ZH�PXVW�DOVR�VXSSO\�WZR�WKLQJV��RQH�IRU�HDFK�LQVWUXFWLRQ�

/'$��WKLV�LQVWUXFWLRQ�LV�VLPLODU�WR�WKH�VRXUFH�RI�D�029�LQVWUXFWLRQ��7KLV�LV�ZKHUH�WKH

GDWD�ZH�ZDQW�WR�PRYH�LV�ORFDWHG��:H�FRXOG�ZULWH�D�FRQVWDQW�KHUH�������IRU�H[DPSOH��

7KLV�ZRXOG�PHDQ�RXU�VRXUFH�GDWD�LV�WKH�QXPEHU�������:H�FRXOG�DOVR�ZULWH�D�ORFDWLRQ

RU� DGGUHVV� RI�ZKHUH� WKH� GDWD�ZH�ZDQW� WR�PRYH� LV� ORFDWHG�� ,I�ZH�ZURWH�'0���� WKLV

ZRXOG�PRYH�WKH�GDWD�WKDW�LV�ORFDWHG�LQ�GDWD�PHPRU\�����

67$��WKLV�LQVWUXFWLRQ�LV�VLPLODU�WR�WKH�GHVWLQDWLRQ�RI�D�029�LQVWUXFWLRQ��:H�ZULWH�DQ

DGGUHVV�KHUH��)RU�H[DPSOH�LI�ZH�ZULWH�'0����KHUH�WKH�GDWD�ZRXOG�EH�PRYHG�LQWR�GDWD

PHPRU\������:H�FRXOG�DOVR�ZULWH������KHUH��7KLV�ZRXOG�PHDQ�WKDW�WKH�GDWD�ZRXOG�EH

PRYHG�WR�WKH�SK\VLFDO�RXWSXWV�������ZRXOG�KDYH�WKH�OHDVW�VLJQLILFDQW�ELW�������ZRXOG

KDYH�WKH�QH[W�ELW���������ZRXOG�KDYH�WKH�PRVW�VLJQLILFDQW�ELW��7KLV�ZRXOG�EH�XVHIXO�LI

Page 39: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

ZH�KDG�D�ELQDU\�GLVSOD\�FRQQHFWHG�WR�WKH�RXWSXWV�DQG�ZH�ZDQWHG�WR�GLVSOD\�WKH�YDOXH

LQVLGH�D�FRXQWHU�IRU�WKH�PDFKLQH�RSHUDWRU�DW�DOO�WLPHV��IRU�H[DPSOH��

7KH�ODGGHU�GLDJUDP�WR�GR�WKLV�ZRXOG�ORRN�VLPLODU�WR�

+HUH�DJDLQ�\RX�ZLOO�QRWLFH�WKDW�ZH�DUH�XVLQJ�D�RQH�VKRW�VR�WKDW�WKH�PRYH�RQO\�RFFXUV

RQFH�IRU�HDFK�WLPH�LQSXW������EHFRPHV�WUXH��,Q�WKLV�ODGGHU�ZH�DUH�PRYLQJ�WKH�FRQVWDQW

����� LQWR� GDWD�PHPRU\� �����7KH� ���� LV� XVHG� E\� VRPH�PDQXIDFWXUHV� WR� V\PEROL]H� D

GHFLPDO� QXPEHU�� ,I� ZH� MXVW� XVHG� ����� WKLV� SOF� ZRXOG� WKLQN� LW� PHDQW� DGGUHVV� �����

3/&V�DUH�DOO�WKH�VDPH����EXW�WKH\�DUH�DOO�GLIIHUHQW�

:H� FDQ� WKLQN� RI� WKLV� LQVWUXFWLRQ� DV� WKH� JDWHZD\� WR� DGYDQFHG� LQVWUXFWLRQV�� ,P� VXUH

\RXOO�ILQG�LW�XVHIXO�DQG�LQYDOXDEOH�DV�ZHOO�VHH�LQ�IXWXUH��0DQ\�DGYDQFHG�IXQFWLRQV�DUH

LPSRVVLEOH�ZLWKRXW�WKLV�LQVWUXFWLRQ�

0DWK�,QVWUXFWLRQVKWWS���ZZZ�SOFV�QHW�PDWK���KWP

/HWV� QRZ� ORRN� DW� XVLQJ� VRPH�EDVLF�PDWK� IXQFWLRQV� RQ� RXU� GDWD��0DQ\� WLPHV� LQ� RXU

DSSOLFDWLRQV�ZH�PXVW� H[HFXWH� VRPH� W\SH� RI�PDWKHPDWLFDO� IRUPXOD� RQ� RXU� GDWD�� ,WV� D

UDUH�RFFXUUHQFH�ZKHQ�RXU�GDWD�LV�DFWXDOO\�H[DFWO\�ZKDW�ZH�QHHGHG�

$V�DQ�H[DPSOH��OHWV�VD\�ZH�DUH�PDQXIDFWXULQJ�ZLGJHWV��:H�GRQW�ZDQW� WR�GLVSOD\�WKH

WRWDO� QXPEHU�ZHYH�PDGH� WRGD\�� EXW� UDWKHU�ZH�ZDQW� WR� GLVSOD\� KRZ�PDQ\�PRUH�ZH

QHHG� WR�PDNH� WRGD\� WR�PHHW�RXU�TXRWD��/HWV� VD\�RXU�TXRWD� IRU� WRGD\� LV� �����SLHFHV�

:HOO�VD\�;�LV�RXU�FXUUHQW�SURGXFWLRQ��7KHUHIRUH��ZH�FDQ�ILJXUH�WKDW������; ZLGJHWV

OHIW�WR�PDNH��7R�LPSOHPHQW�WKLV�IRUPXOD�ZH�REYLRXVO\�QHHG�VRPH�PDWK�FDSDELOLW\�

,Q�JHQHUDO��SOFV�DOPRVW�DOZD\V�LQFOXGH�WKHVH�PDWK�IXQFWLRQV�

$GGLWLRQ��7KH� FDSDELOLW\� WR� DGG�RQH�SLHFH�RI�GDWD� WR� DQRWKHU�� ,W� LV� FRPPRQO\� FDOOHG

$''�

6XEWUDFWLRQ��7KH�FDSDELOLW\�WR�VXEWUDFW�RQH�SLHFH�RI�GDWD�IURP�DQRWKHU��,W�LV�FRPPRQO\

FDOOHG�68%�

0XOWLSOLFDWLRQ��7KH�FDSDELOLW\�WR�PXOWLSO\�RQH�SLHFH�RI�GDWD�E\�DQRWKHU��,W�LV�FRPPRQO\

FDOOHG�08/�

Page 40: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

'LYLVLRQ�� 7KH� FDSDELOLW\� WR� GLYLGH� RQH� SLHFH� RI� GDWD� IURP� DQRWKHU�� ,W� LV� FRPPRQO\

FDOOHG�',9�

$V�ZH�VDZ�ZLWK�WKH�029�LQVWUXFWLRQ�WKHUH�DUH�JHQHUDOO\�WZR�FRPPRQ�PHWKRGV�XVHG

E\�WKH�PDMRULW\�RI�SOF�PDNHUV��7KH�ILUVW�PHWKRG�LQFOXGHV�D�VLQJOH�LQVWUXFWLRQ�WKDW�DVNV

XV�IRU�D�IHZ�NH\�SLHFHV�RI�LQIRUPDWLRQ��7KLV�PHWKRG�W\SLFDOO\�UHTXLUHV�

6RXUFH�$��7KLV�LV�WKH�DGGUHVV�RI�WKH�ILUVW�SLHFH�RI�GDWD�ZH�ZLOO�XVH�LQ�RXU�IRUPXOD��,Q

RWKHU�ZRUGV�LWV�WKH�ORFDWLRQ�LQ�PHPRU\�RI�ZKHUH�WKH�ILUVW��QXPEHU��LV� WKDW�ZH�XVH�LQ

WKH�IRUPXOD�

6RXUFH�%��7KLV�LV�WKH�DGGUHVV�RI�WKH�VHFRQG�SLHFH�RI�GDWD�ZH�ZLOO�XVH�LQ�RXU�IRUPXOD��,Q

RWKHU�ZRUGV�LWV�WKH�ORFDWLRQ�LQ�PHPRU\�RI�ZKHUH�WKH�VHFRQG��QXPEHU��LV�WKDW�ZH�XVH�LQ

WKH� IRUPXOD�� �127(�� W\SLFDOO\�ZH�FDQ�RQO\�ZRUN�ZLWK���SLHFHV�RI�GDWD�DW� D� WLPH�� ,Q

RWKHU� ZRUGV� ZH� FDQW� ZRUN� GLUHFWO\� ZLWK� D� IRUPXOD� OLNH� �������:H� ZRXOG� KDYH� WR

EUHDN�LW�XS�LQWR�SLHFHV��/LNH���� ;�WKHQ�;�� �RXU�UHVXOW�

'HVWLQDWLRQ�� 7KLV� LV� WKH� DGGUHVV� ZKHUH� WKH� UHVXOW� RI� RXU� IRUPXOD� ZLOO� EH� SXW�� )RU

H[DPSOH��LI���� ����,�KRSH�LW�VWLOO�GRHV����� WKH���ZRXOG�DXWRPDWLFDOO\�EH�SXW� LQWR�WKLV

GHVWLQDWLRQ�PHPRU\�ORFDWLRQ�

7KH�LQVWUXFWLRQV�DERYH�W\SLFDOO\�KDYH�D�V\PERO�WKDW�ORRNV�OLNH�

2I�FRXUVH��WKH�ZRUG�$''�ZRXOG�EH�UHSODFHG�E\�68%��08/��',9��HWF��,Q�WKLV�V\PERO�

7KH� VRXUFH� $� LV� '0����� WKH� VRXUFH� %� LV� '0���� DQG� WKH� GHVWLQDWLRQ� LV� '0����

7KHUHIRUH��WKH�IRUPXOD�LV�VLPSO\�ZKDWHYHU�YDOXH�LV�LQ�'0������ZKDWHYHU�YDOXH�LV�LQ

'0�����7KH�UHVXOW�LV�DXWRPDWLFDOO\�VWRUHG�LQWR�'0����

+HUHV�KRZ�WR�XVH�PDWK�IXQFWLRQV�RQ�D�ODGGHU�GLDJUDP�

3OHDVH�QRWH�WKDW�RQFH�DJDLQ�ZH�DUH�XVLQJ�D�RQH�VKRW�LQVWUXFWLRQ��$V�ZHYH�VHHQ�EHIRUH�

WKLV�LV�EHFDXVH�LI�ZH�GLGQW�XVH�LW�ZH�ZRXOG�H[HFXWH�WKH�IRUPXOD�RQ�HYHU\�VFDQ��2GGV

DUH� JRRG� WKDW� ZHG� RQO\� ZDQW� WR� H[HFXWH� WKH� IXQFWLRQ� RQH� WLPH� ZKHQ� LQSXW� ����

Page 41: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

EHFRPHV� WUXH�� ,I� ZH� KDG� SUHYLRXVO\� SXW� WKH� QXPEHU� ���� LQWR� '0���� DQG� ���� LQWR

'0�����WKH�QXPEHU�����ZRXOG�EH�VWRUHG�LQ�'0������L�H��������� �����ULJKW""�

7KH�GXDO�LQVWUXFWLRQ�PHWKRG�ZRXOG�XVH�D�V\PERO�VLPLODU�WR

,Q�WKLV�PHWKRG��ZH�JLYH�WKLV�V\PERO�RQO\�WKH�6RXUFH�%�ORFDWLRQ��7KH�6RXUFH�$�ORFDWLRQ

LV� JLYHQ� E\� WKH� /'$� LQVWUXFWLRQ�� 7KH� 'HVWLQDWLRQ� ZRXOG� EH� LQFOXGHG� LQ� WKH� 67$

LQVWUXFWLRQ��+HUHV�D�ODGGHU�GLDJUDP�VKRZLQJ�ZKDW�ZH�PHDQ�

7KH�UHVXOWV�DUH�WKH�VDPH�DV�WKH�VLQJOH�LQVWUXFWLRQ�PHWKRG�VKRZQ�DERYH�

:KDW�ZRXOG�KDSSHQ� LI�ZH�KDG�D� UHVXOW� WKDW�ZDV�JUHDWHU� WKDQ� WKH�YDOXH� WKDW�FRXOG�EH

VWRUHG� LQ� D� PHPRU\� ORFDWLRQ"� 7\SLFDOO\� WKH� PHPRU\� ORFDWLRQV� DUH� ���ELW� ORFDWLRQV�

�PRUH� DERXW� QXPEHU� W\SHV� LQ� D� ODWHU� FKDSWHU�� ,Q� SODLQ� ZRUGV� WKLV�PHDQV� WKDW� LI� WKH

QXPEHU� LV� JUHDWHU� WKDQ� ������ ��A�� ������� LW� LV� WRR� ELJ� WR� ILW�� 7KH� ZH� JHW� ZKDWV

FDOOHG�DQ�RYHUIORZ��7\SLFDOO\�WKH�SOF�WXUQV�RQ�DQ�LQWHUQDO�UHOD\�WKDW�WHOOV�XV�DQ�RYHUIORZ

KDV�KDSSHQHG��'HSHQGLQJ�RQ�WKH�SOF��ZH�ZRXOG�KDYH�GLIIHUHQW�GDWD�LQ�WKH�GHVWLQDWLRQ

ORFDWLRQ�� �'0���� DERYH��0RVW� SOFV� SXW� WKH� UHPDLQGHU� KHUH�� 6RPH� XVH� ���ELW�PDWK

ZKLFK�VROYHV�WKH�SUREOHP���H[FHSW�IRU�UHDOO\�ELJ�QXPEHUV���,I�ZHUH�GRLQJ�GLYLVLRQ��IRU

H[DPSOH��DQG�ZH�GLYLGH�E\�]HUR� �LOOHJDO�� WKH�RYHUIORZ�ELW� W\SLFDOO\� WXUQV�RQ�DV�ZHOO�

6XIILFH� LW� WR� VD\�� FKHFN� WKH� RYHUIORZ� ELW� LQ� \RXU� ODGGHU� DQG� LI� LWV� WUXH� SODQ

DSSURSULDWHO\�

0DQ\� SOFV� DOVR� LQFOXGH� RWKHU� PDWK� FDSDELOLWLHV�� 6RPH� RI� WKHVH� IXQFWLRQV� FRXOG

LQFOXGH�

x� 6TXDUH�URRWV

x� 6FDOLQJ

x� $EVROXWH�YDOXH

x� 6LQH

x� &RVLQH

x� 7DQJHQW

x� 1DWXUDO�ORJDULWKP

x� %DVH����ORJDULWKP

Page 42: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

x� ;A<��;�WR�WKH�SRZHU�RI�<�

x� $UFVLQ��WDQ�FRV�

x� DQG�PRUH����FKHFN�ZLWK�WKH�PDQXIDFWXUHU�WR�EH�VXUH�

6RPH�SOFV� FDQ�XVH� IORDWLQJ�SRLQW�PDWK�DV�ZHOO��)ORDWLQJ�SRLQW�PDWK� LV� VLPSO\�XVLQJ

GHFLPDO�SRLQWV��,Q�RWKHU�ZRUGV��ZH�FRXOG�VD\�WKDW����GLYLGHG�E\���LV�����������IORDWLQJ

SRLQW���2U�ZH�FRXOG�VD\�WKDW����GLYLGHG�E\���LV���ZLWK�D�UHPDLQGHU�RI����ORQJ�GLYLVLRQ��

0DQ\�PLFUR�PLQL�SOFV�GRQW�LQFOXGH�IORDWLQJ�SRLQW�PDWK��0RVW�ODUJHU�V\VWHPV�W\SLFDOO\

GR��$V�DOZD\V�� WKH�WKHRU\�LV�DOZD\V�WKH�VDPH��KRZ�ZH�LPSOHPHQW� LW� LV�DQRWKHU�VWRU\�

8QGHUVWDQG�WKH�WKHRU\�DQG�ZH�FDQ�DOZD\V�OHDUQ�KRZ�RXU�PDQXIDFWXUHU�RI�FKRLFH�GRHV

LW�

1XPEHU�6\VWHPVKWWS���ZZZ�SOFV�QHW�QXPEHUV���KWP

%HIRUH� ZH� JHW� WRR� IDU� DKHDG� RI� RXUVHOYHV�� OHWV� WDNH� D� ORRN� DW� WKH� YDULRXV� QXPEHU

V\VWHPV� XVHG� E\� SOFV�� 0DQ\� QXPEHU� V\VWHPV� DUH� XVHG� E\� SOFV�� 0DQ\� DUH� DFWXDO

DGGUHVVHG�XVLQJ�ELQDU\�FRGH�ZKLOH�RFWDO�DQG�KH[DGHFLPDO�V\VWHPV�DUH�DOVR�FRPPRQ�

/HWV�ORRN�DW�HDFK�V\VWHP��$V�ZH�GR��FRQVLGHU�WKH�IROORZLQJ�IRUPXOD��0DWK�DJDLQ�����

1EDVH �'GLJLW5AXQLW�������'�5A����'�5A��ZKHUH�' WKH�YDOXH�RI�WKH�GLJLW�DQG�5 ��

RI�GLJLW�V\PEROV�XVHG�LQ�WKH�JLYHQ�QXPEHU�V\VWHP��7KH��A��PHDQV��WR�WKH�SRZHU�RI��

$V� \RXOO� UHFDOO� DQ\� QXPEHU� UDLVHG� WR� WKH� SRZHU� RI� �� LV� ��� ��A� ���� ��A�� LV

��[�� ����� ��A�� LV� ��[��[�� ������ ��A�� LV� ��[��[��[�� ��������� 7KLV� OHWV� XV

FRQYHUW�IURP�DQ\�QXPEHU�V\VWHP�EDFN�LQWR�GHFLPDO��:KDW"""�5HDG�RQ���

'HFLPDO��7KLV� LV� WKH�QXPEHULQJ�V\VWHP�ZH�XVH�LQ�HYHU\GD\�OLIH���ZHOO�PRVW�RI�XV�GR

DQ\ZD\���:H� FDQ� WKLQN� RI� WKLV� DV� EDVH� ��� FRXQWLQJ��:H� FDQ� UHIHU� WR� LW� DV� EDVH� ��

EHFDXVH� HDFK� GLJLW� FDQ� KDYH� ��� GLIIHUHQW� VWDWHV�� �L�H�� ����� 6LQFH� WKLV� LV� QRW� HDV\� WR

LPSOHPHQW� LQ�DQ�HOHFWURQLF� V\VWHP� LW� LV� VHOGRP�� LI� HYHU�� XVHG�� ,I�ZH�XVH� WKH� IRUPXOD

DERYH� ZH� FDQ� ILQG� RXW� ZKDW� WKH� QXPEHU� ���� LV�� )URP� WKH� IRUPXOD�� 1EDVH

'GLJLW5AXQLW� ������ '�5A�� �� '�5A�� ZH� KDYH� �VLQFH� ZHUH� GRLQJ� EDVH� ���� 5 ���

1�� '���A����'���A����'���A�� �� ������� ������ �� ������������� �����

%LQDU\�� 7KLV� LV� WKH� QXPEHULQJ� V\VWHP� FRPSXWHUV� DQG� SOFV� XVH�� ,W� ZDV� IDU� HDVLHU� WR

GHVLJQ�D�V\VWHP�LQ�ZKLFK�RQO\���QXPEHUV� ���DQG����DUH�PDQLSXODWHG��L�H��XVHG���7KH

ELQDU\�V\VWHP�XVHV�WKH�VDPH�EDVLF�SULQFLSOHV�DV�WKH�GHFLPDO�V\VWHP��,Q�GHFLPDO�ZH�KDG

��� GLJLWV�� ,Q� ELQDU\� ZH� RQO\� KDYH� �� GLJLWV� ��� DQG� ���� 6R�� LQ� GHFLPDO� ZH� FRXQW�

���������������������DQG�LQVWHDG�RI�JRLQJ�EDFN�WR�]HUR�ZH�VWDUW�D�QHZ�GLJLW�DQG�WKHQ�VWDUW

IURP��� LQ� WKH� RULJLQDO� GLJLW� ORFDWLRQ�� ,Q� RWKHU�ZRUGV��ZH� VWDUW� E\� SODFLQJ� D� �� LQ� WKH

VHFRQG� GLJLW� ORFDWLRQ� DQG� EHJLQ� FRXQWLQJ� DJDLQ� LQ� WKH� RULJLQDO� ORFDWLRQ� OLNH� WKLV

����������������:KHQ�DJDLQ�ZH�KLW����ZH�LQFUHPHQW�WKH�VHFRQG�GLJLW�DQG�VWDUW�FRXQWLQJ

IURP��� DJDLQ� LQ� WKH� RULJLQDO� GLJLW� ORFDWLRQ�� /LNH� ���������������� RI� FRXUVH� WKLV� NHHSV

UHSHDWLQJ��$QG�ZKHQ�ZH�UXQ�RXW�RI�GLJLWV�LQ�WKH�VHFRQG�GLJLW�ORFDWLRQ�ZH�FUHDWH�D�WKLUG

GLJLW� DQG� DJDLQ� VWDUW� IURP� VFUDWFK�� �L�H�� ���� ����� ����� ��������%LQDU\�ZRUNV� WKH� VDPH

ZD\��:H�VWDUW�ZLWK���WKHQ����6LQFH�WKHUH�LV�QR���LQ�ELQDU\�ZH�PXVW�FUHDWH�D�QHZ�GLJLW�

7KHUHIRUH�ZH�KDYH���� ��� ���� ��� DQG� DJDLQ�ZH� UXQ� RXW� RI� URRP��7KHUHIRUH�ZH� FUHDWH

DQRWKHU�GLJLW� OLNH���������������������$JDLQ�ZH� UDQ�RXW�RI� URRP�VR�ZH�DGG� DQRWKHU

Page 43: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

GLJLW����'R� \RX� JHW� WKH� LGHD""�7KH� JHQHUDO� FRQYHUVLRQ� IRUPXOD�PD\� FOHDU� WKLQJV� XS�

1EDVH �'GLJLW5AXQLW�������'�5A����'�5A���6LQFH�ZHUH�QRZ�GRLQJ�ELQDU\�RU�EDVH���

5 ���/HWV� WU\� WR� FRQYHUW� WKH�ELQDU\�QXPEHU������ EDFN� LQWR� GHFLPDO��1�� '��A���

'��A����'��A����'��A�� � ����� ����� ����� �� ������������ �����LI�\RX�GRQW�VHH

ZKHUH�WKH�ZKLWH��������DQG���FDPH�IURP��UHIHU�WR�WKH�WDEOH�EHORZ���1RZ�ZH�FDQ�VHH�WKDW

ELQDU\� ����� LV� WKH� VDPH� DV� GHFLPDO� ���� 7U\� WUDQVODWLQJ� ELQDU\� �����<RX� VKRXOG� JHW

GHFLPDO����7U\�ELQDU\��������<RX�VKRXOG�JHW�GHFLPDO����

+HUHV�D�VLPSOH�ELQDU\�FKDUW�IRU�\RXU�UHIHUHQFH��7KH�WRS�URZ�VKRZV�SRZHUV�RI���ZKLOH

WKH�ERWWRP�URZ�VKRZV�WKHLU�HTXLYDOHQW�GHFLPDO�YDOXH�

%LQDU\�1XPEHU�&RQYHUVLRQV

�A�� �A�� �A�� �A�� �A�� �A�� �A� �A� �A� �A� �A� �A� �A� �A� �A� �A�

����� ����� ���� ���� ���� ���� ��� ��� ��� �� �� �� � � � �

2FWDO��7KH�ELQDU\�QXPEHU�V\VWHP�UHTXLUHV�D�WRQ�RI�GLJLWV�WR�UHSUHVHQW�D�ODUJH�QXPEHU�

&RQVLGHU�WKDW�ELQDU\����������LV�RQO\�GHFLPDO������$�GHFLPDO�QXPEHU�OLNH����������

��� PLOOLRQ��� ZRXOG� QHHG� D� ORW� RI� ELQDU\� GLJLWV��� 3OXV� LWV� DOVR� KDUG� IRU� KXPDQV� WR

PDQLSXODWH� VXFK� QXPEHUV�ZLWKRXW�PDNLQJ�PLVWDNHV�� 7KHUHIRUH� VHYHUDO� FRPSXWHU�SOF

PDQXIDFWXUHUV� VWDUWHG� WR� LPSOHPHQW� WKH� RFWDO� QXPEHU� V\VWHP�� 7KLV� V\VWHP� FDQ� EH

WKRXJKW� RI� DV� EDVH�� VLQFH� LW� FRQVLVWV� RI� �� GLJLWV�� ������������������ 6R� ZH� FRXQW� OLNH

��������������������������������������������������� 8VLQJ� WKH� IRUPXOD� DJDLQ�� ZH� FDQ

FRQYHUW�DQ�RFWDO�QXPEHU�WR�GHFLPDO�TXLWH�HDVLO\��1EDVH �'GLJLW5AXQLW�������'�5A���

'�5A��6R�RFWDO�����ZRXOG�EH� �� �UHPHPEHU� WKDW�KHUH�5 ���1�� �'��A����'��A���

'��A�� �� ������ ����� � ����������� ������LI�\RX�GRQW�VHH�ZKHUH�WKH�ZKLWH�����

DQG���FDPH�IURP��UHIHU�WR�WKH�WDEOH�EHORZ���1RZ�ZH�FDQ�VHH�WKDW�RFWDO�����LV�WKH�VDPH

DV�GHFLPDO������7U\� WUDQVODWLQJ�RFWDO�����<RX�VKRXOG�JHW�GHFLPDO�����7U\�RFWDO� ����

<RX�VKRXOG�JHW�GHFLPDO����

+HUHV�D�VLPSOH�RFWDO�FKDUW�IRU�\RXU�UHIHUHQFH��7KH�WRS�URZ�VKRZV�SRZHUV�RI���ZKLOH

WKH�ERWWRP�URZ�VKRZV�WKHLU�HTXLYDOHQW�GHFLPDO�YDOXH�

2FWDO�1XPEHU�&RQYHUVLRQV

�A� �A� �A� �A� �A� �A� �A� �A� �A�

�������� ������� ������ ����� ���� ��� �� � �

/DVWO\��WKH�RFWDO�V\VWHP�LV�D�FRQYHQLHQW�ZD\�IRU�XV�WR�H[SUHVV�RU�ZULWH�ELQDU\�QXPEHUV

LQ�SOF� V\VWHPV��$�ELQDU\� QXPEHU�ZLWK� D� ODUJH� QXPEHU� RI� GLJLWV� FDQ� EH� FRQYHQLHQWO\

ZULWWHQ� LQ� DQ� RFWDO� IRUP� ZLWK� IHZHU� GLJLWV�� 7KLV� LV� EHFDXVH� �� RFWDO� GLJLW� DFWXDOO\

UHSUHVHQWV���ELQDU\�GLJLWV��%HOLHYH�XV�WKDW�ZKHQ�ZH�VWDUW�ZRUNLQJ�ZLWK�UHJLVWHU�GDWD�RU

DGGUHVV�ORFDWLRQV�LQ�WKH�DGYDQFHG�FKDSWHUV�LW�EHFRPHV�D�JUHDW�ZD\�RI�H[SUHVVLQJ�GDWD�

7KH�IROORZLQJ�FKDUW�VKRZV�ZKDW�ZHUH�UHIHUULQJ�WR�

%LQDU\�1XPEHU�ZLWK�LWV�RFWDO�HTXLYDOHQW

� � � � � � � � � � � � � � � �

� � � � � �

Page 44: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

)URP�WKH�FKDUW�ZH�FDQ�VHH� WKDW�ELQDU\������������������ LV�RFWDO��������� �GHFLPDO

�������$V�ZH�FDQ�VHH��ZKHQ�ZH�WKLQN�RI�UHJLVWHUV��LWV�HDVLHU�WR�WKLQN�LQ�RFWDO�WKDQ�LQ

ELQDU\��$V�\RXOO�VRRQ�VHH�WKRXJK��KH[DGHFLPDO�LV�WKH�EHVW�ZD\�WR�WKLQN���UHDOO\�

+H[DGHFLPDO�7KH�ELQDU\�QXPEHU� V\VWHP� UHTXLUHV� D� WRQ�RI�GLJLWV� WR� UHSUHVHQW� D� ODUJH

QXPEHU�� 7KH� RFWDO� V\VWHP� LPSURYHV� XSRQ� WKLV�� 7KH� KH[DGHFLPDO� V\VWHP� LV� WKH� EHVW

VROXWLRQ�KRZHYHU��EHFDXVH�LW�DOORZV�XV� WR�XVH�HYHQ�OHVV�GLJLWV��,W� LV� WKHUHIRU� WKH�PRVW

SRSXODU� QXPEHU� V\VWHP� XVHG� ZLWK� FRPSXWHUV� DQG� SOFV�� �ZH� VKRXOG� OHDUQ� HDFK� RQH

WKRXJK��7KH�KH[DGHFLPDO�V\VWHP�LV�DOVR�UHIHUUHG�WR�DV�EDVH����RU�MXVW�VLPSO\�KH[��$V

WKH� QDPH� EDVH� ��� LPSOLHV�� LW� KDV� ��� GLJLWV�� 7KH� GLJLWV� DUH� ��������������������$�%�&�

'�(�)�� 6R� ZH� FRXQW� OLNH� ��������������������$�%�&�'�(�)�������� ����������$��%�

�&��'��(��)����������$��%��&��'��(��)������� 8VLQJ� WKH� IRUPXOD� DJDLQ�� ZH� FDQ

FRQYHUW� D� KH[� QXPEHU� WR� GHFLPDO� TXLWH� HDVLO\�� 1EDVH � 'GLJLW5AXQLW� ������ '�5A�� �

'�5A��6R�KH[��$��ZRXOG�EH���UHPHPEHU�KHUH�WKDW�5 ����1�� �'���A����'$��A���

'���A�� �� ������$��$ GHFLPDO���� ������ � ������������� �������LI�\RX�GRQW

VHH�ZKHUH�WKH�ZKLWH�������DQG���FDPH�IURP��UHIHU�WR�WKH�WDEOH�EHORZ���1RZ�ZH�FDQ�VHH

WKDW� KH[� )))� LV� WKH� VDPH� DV� GHFLPDO� ������ 7U\� WUDQVODWLQJ� KH[� ���� <RX� VKRXOG� JHW

GHFLPDO������7U\�KH[������<RX�VKRXOG�JHW�GHFLPDO�����

+HUHV�D�VLPSOH�KH[�FKDUW�IRU�\RXU�UHIHUHQFH��7KH�WRS�URZ�VKRZV�SRZHUV�RI����ZKLOH

WKH� ERWWRP� URZ� VKRZV� WKHLU� HTXLYDOHQW� GHFLPDO� YDOXH�� 1RWLFH� WKDW� WKH� QXPEHUV� JHW

ODUJH�UDWKHU�TXLFNO\�

+H[�1XPEHU�&RQYHUVLRQV

��A� ��A� ��A� ��A� ��A� ��A� ��A� ��A� ��A�

���������� ��������� �������� ������� ����� ���� ��� �� �

)LQDOO\��WKH�KH[�V\VWHP�LV�SHUKDSV�WKH�PRVW�FRQYHQLHQW�ZD\�IRU�XV�WR�H[SUHVV�RU�ZULWH

ELQDU\�QXPEHUV�LQ�SOF�V\VWHPV��$�ELQDU\�QXPEHU�ZLWK�D�ODUJH�QXPEHU�RI�GLJLWV�FDQ�EH

FRQYHQLHQWO\�ZULWWHQ�LQ�KH[�IRUP�ZLWK� IHZHU�GLJLWV� WKDQ�RFWDO��7KLV� LV�EHFDXVH���KH[

GLJLW� DFWXDOO\� UHSUHVHQWV� �� ELQDU\� GLJLWV��%HOLHYH� LW� WKDW�ZKHQ�ZH� VWDUW�ZRUNLQJ�ZLWK

UHJLVWHU�GDWD�RU�DGGUHVV�ORFDWLRQV�LQ�WKH�DGYDQFHG�FKDSWHUV�LW�EHFRPHV�WKH�EHVW�ZD\�RI

H[SUHVVLQJ�GDWD��7KH�IROORZLQJ�FKDUW�VKRZV�ZKDW�ZHUH�UHIHUULQJ�WR�

%LQDU\�1XPEHU�ZLWK�LWV�KH[�HTXLYDOHQW

� � � � � � � � � � � � � � � �

� � $ �

)URP� WKH� FKDUW� ZH� FDQ� VHH� WKDW� ELQDU\� ����������������� LV� KH[� ��$��� �GHFLPDO

�������$V�ZH�FDQ�VHH��ZKHQ�ZH�WKLQN�RI�UHJLVWHUV��LWV�IDU�HDVLHU�WR�WKLQN�LQ�KH[�WKDQ�LQ

ELQDU\�RU�RFWDO����GLJLWV�JRHV�D�ORQJ�ZD\�DIWHU�VRPH�SUDFWLFH�

Page 45: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

%RROHDQ�0DWKKWWS���ZZZ�SOFV�QHW�ERROHDQ���KWP

/HWV�QRZ�WDNH�D�ORRN�DW�VRPH�VLPSOH��ERROHDQ�PDWK���%RROHDQ�PDWK�OHWV�XV�GR�VRPH

YDU\� EDVLF� IXQFWLRQV� ZLWK� WKH� ELWV� LQ� RXU� UHJLVWHUV�� 7KHVH� EDVLF� IXQFWLRQV� W\SLFDOO\

LQFOXGH�$1'��25�DQG�;25�IXQFWLRQV��(DFK�LV�GHVFULEHG�EHORZ�

�����$1'��7KLV�IXQFWLRQ�HQDEOHV�XV�WR�XVH�WKH�WUXWK�WDEOH�EHORZ��+HUH��ZH�FDQ�VHH�WKDW

WKH�$1'�IXQFWLRQ�LV�YHU\�PXFK�UHODWHG�WR�PXOWLSOLFDWLRQ��:H�VHH�WKLV�EHFDXVH�WKH�RQO\

WLPH�WKH�5HVXOW�LV�WUXH��L�H�����LV�ZKHQ�ERWK�RSHUDWRUV�$�$1'�%�DUH�WUXH��L�H������7KH

$1'�LQVWUXFWLRQ�LV�XVHIXO�ZKHQ�\RXU�SOF�GRHVQW�KDYH�D�PDVNLQJ�IXQFWLRQ��2K�\HDK��D

PDVNLQJ�IXQFWLRQ�HQDEOHV�D�ELW�LQ�D�UHJLVWHU�WR�EH��OHIW�DORQH��ZKHQ�ZRUNLQJ�RQ�D�ELW

OHYHO��7KLV�LV�VLPSO\�EHFDXVH�DQ\�ELW�WKDW�LV�$1'HG�ZLWK�LWVHOI�ZLOO�UHPDLQ�WKH�YDOXH�LW

FXUUHQWO\�LV��)RU�H[DPSOH��LI�\RX�ZDQWHG�WR�FOHDU�RQO\����ELWV�LQ�D����ELW�UHJLVWHU�\RX

PLJKW� $1'� WKH� UHJLVWHU� ZLWK� �V� HYHU\ZKHUH� H[FHSW� LQ� WKH� �� ELWV� \RX� ZDQWHG� WR

PDLQWDLQ�WKH�VWDWXV�RI��6HH�WKH�WUXWK�WDEOH�EHORZ�WR�ILJXUH�RXW�ZKDW�ZH�PHDQ�����$1'��

������$1'��� ������5HVXOW� �$�$1'�%

$ % 5HVXOW

� � �

� � �

� � �

� � �

�����25��7KLV�IXQFWLRQV�EDVHG�XSRQ�WKH�WUXWK�WDEOH�EHORZ��+HUH��ZH�FDQ�VHH�WKDW�WKH�25

IXQFWLRQ�LV�YHU\�PXFK�UHODWHG�WR�DGGLWLRQ��:H�VHH�WKLV�EHFDXVH�WKH�RQO\�WLPH�WKH�5HVXOW

LV�WUXH��L�H�����LV�ZKHQ�RSHUDWRU�$�25�%�LV�WUXH��L�H������2EYLRXVO\��ZKHQ�WKH\�DUH�ERWK

WUXH�WKH�UHVXOW�LV�WUXH���,I�$�25�%�LV�WUXH����5HVXOW� �$�25�%

$ % 5HVXOW

� � �

� � �

� � �

� � �

�����(;25��7KLV�IXQFWLRQ�HQDEOHV�XV�WR�XVH�WKH�WUXWK�WDEOH�EHORZ��+HUH��ZH�FDQ�VHH�WKDW

WKH�(;25��;25��IXQFWLRQ�LV�QRW�UHODWHG�WR�DQ\WKLQJ�,�FDQ�WKLQN�RI����$Q�HDV\�ZD\�WR

UHPHPEHU�WKH�UHVXOWV�RI�WKLV�IXQFWLRQ�LV�WR�WKLQN�WKDW�$�DQG�%�PXVW�EH�RQH�RU�WKH�RWKHU

FDVH��H[FOXVLYHO\��+XK""�,Q�RWKHU�ZRUGV��WKH\�PXVW�EH�RSSRVLWHV�RI�HDFK�RWKHU��:KHQ

WKH\�DUH�ERWK�WKH�VDPH��L�H��$ %��WKH�UHVXOW�LV�IDOVH��L�H������7KLV�LV�VRPHWLPHV�XVHIXO

ZKHQ�\RX�ZDQW�WR�FRPSDUH�ELWV�LQ���UHJLVWHUV�DQG�KLJKOLJKW�ZKLFK�ELWV�DUH�GLIIHUHQW��,WV

DOVR�QHHGHG�ZKHQ�ZH�FDOFXODWH� VRPH�FKHFNVXPV��$�FKHFNVXP� LV� FRPPRQO\�XVHG� DV

HUURU� FKHFNLQJ� LQ� VRPH� FRPPXQLFDWLRQV� SURWRFROV�� �0RUH� RQ� WKDW� LQ� D� IXWXUH

FKDSWHU��5HVXOW� �$�;25�%

Page 46: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

$ % 5HVXOW

� � �

� � �

� � �

� � �

7KH�LQVWUXFWLRQV�DUH�FRPPRQO\�FDOOHG�$1'��$1'$��$1':��25��25$��25:��;25�

(25$�;25:��$V�ZH�VDZ�ZLWK�WKH�029�LQVWUXFWLRQ�WKHUH�DUH�JHQHUDOO\�WZR�FRPPRQ

PHWKRGV� XVHG� E\� WKH� PDMRULW\� RI� SOF� PDNHUV�� 7KH� ILUVW� PHWKRG� LQFOXGHV� D� VLQJOH

LQVWUXFWLRQ� WKDW� DVNV� XV� IRU� D� IHZ� NH\� SLHFHV� RI� LQIRUPDWLRQ�� 7KLV�PHWKRG� W\SLFDOO\

UHTXLUHV�

�����6RXUFH�$��7KLV�LV�WKH�DGGUHVV�RI�WKH�ILUVW�SLHFH�RI�GDWD�ZH�ZLOO�XVH��,Q�RWKHU�ZRUGV

LWV�WKH�ORFDWLRQ�LQ�PHPRU\�RI�ZKHUH�WKH�$�LV�

�����6RXUFH� %�� 7KLV� LV� WKH� DGGUHVV� RI� WKH� VHFRQG� SLHFH� RI� GDWD� ZH�ZLOO� XVH�� ,Q� RWKHU

ZRUGV�LWV�WKH�ORFDWLRQ�LQ�PHPRU\�RI�ZKHUH�WKH�%�LV�

�����'HVWLQDWLRQ�� 7KLV� LV� WKH� DGGUHVV�ZKHUH� WKH� UHVXOW� ZLOO� EH� SXW�� )RU� H[DPSOH�� LI� $

$1'�%� � �� WKH� UHVXOW� ����ZRXOG� DXWRPDWLFDOO\� EH� SXW� LQWR� WKLV� GHVWLQDWLRQ�PHPRU\

ORFDWLRQ�

7KH�LQVWUXFWLRQV�DERYH�W\SLFDOO\�KDYH�D�V\PERO�WKDW�ORRNV�OLNH�

2I� FRXUVH�� WKH�ZRUG�$1'�ZRXOG� EH� UHSODFHG� E\�25� RU� ;25�� ,Q� WKLV� V\PERO�� 7KH

VRXUFH�$�LV�'0�����WKH�VRXUFH�%�LV�'0����DQG�WKH�GHVWLQDWLRQ�LV�'0�����7KHUHIRUH�

ZH�KDYH� VLPSO\�FUHDWHG� WKH�HTXDWLRQ�'0����$1'�'0���� �'0�����7KH� UHVXOW� LV

DXWRPDWLFDOO\� VWRUHG� LQWR�'0����� �+HUHV� KRZ� WR�XVH�ERROHDQ� IXQFWLRQV�RQ� D� ODGGHU

GLDJUDP�

3OHDVH�QRWH�WKDW�RQFH�DJDLQ�ZH�DUH�XVLQJ�D�RQH�VKRW�LQVWUXFWLRQ��$V�ZHYH�VHHQ�EHIRUH�

WKLV�LV�EHFDXVH�LI�ZH�GLGQW�XVH�LW��ZH�ZRXOG�H[HFXWH�WKH�IRUPXOD�RQ�HYHU\�VFDQ��2GGV

DUH� JRRG� WKDW� ZHG� RQO\� ZDQW� WR� H[HFXWH� WKH� IXQFWLRQ� RQH� WLPH� ZKHQ� LQSXW� ����

EHFRPHV�WUXH�

7KH�GXDO�LQVWUXFWLRQ�PHWKRG�ZRXOG�XVH�D�V\PERO�VLPLODU�WR

Page 47: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

,Q�WKLV�PHWKRG��ZH�JLYH�WKLV�V\PERO�RQO\�WKH�6RXUFH�%�ORFDWLRQ��7KH�6RXUFH�$�ORFDWLRQ

LV� JLYHQ� E\� WKH� /'$� LQVWUXFWLRQ�� 7KH� 'HVWLQDWLRQ� ZRXOG� EH� LQFOXGHG� LQ� WKH� 67$

LQVWUXFWLRQ��+HUHV�D�ODGGHU�GLDJUDP�VKRZLQJ�ZKDW�ZH�PHDQ�

7KH�UHVXOWV�DUH�WKH�VDPH�DV�WKH�VLQJOH�LQVWUXFWLRQ�PHWKRG�VKRZQ�DERYH�

'&�,QSXWVKWWS���ZZZ�SOFV�QHW�GFLQ���KWP

/HWV�QRZ�WDNH�D�ORRN�DW�KRZ�WKH�LQSXW�FLUFXLWV�RI�D�SOF�ZRUN��WKLV�ZLOO�JLYH�XV�D�EHWWHU

XQGHUVWDQGLQJ�RI�KRZ�ZH�VKRXOG�ZLUH�WKHP�XS��%DG�WKLQJV�FDQ�KDSSHQ�LI�ZH�ZLUH�WKHP

XS�LQFRUUHFWO\��7\SLFDOO\��GF�LQSXW�PRGXOHV�DUH�DYDLODEOH�WKDW�ZLOO�ZRUN�ZLWK�����������

DQG����YROWV��%H� VXUH� WR�SXUFKDVH� WKH�RQH� WKDW� ILWV� \RXU�QHHGV�EDVHG� XSRQ� WKH� LQSXW

GHYLFHV�\RX�ZLOO�XVH�

:HOO� ILUVW� ORRN� DW� KRZ� WKH� GF� LQSXWV�ZRUN��'&� LQSXW�PRGXOHV� DOORZ� XV� WR� FRQQHFW

HLWKHU�313��VRXUFLQJ��RU�131��VLQNLQJ��WUDQVLVWRU�W\SH�GHYLFHV�WR�WKHP��,I�ZH�DUH�XVLQJ

D�UHJXODU�VZLWFK��L�H��WRJJOH�RU�SXVKEXWWRQ��HWF���ZH�W\SLFDOO\�GRQW�KDYH�WR�ZRUU\�DERXW

ZKHWKHU�ZH�ZLUH�LW�DV�131�RU�313��:H�VKRXOG�QRWH�WKDW�PRVW�SOFV�ZRQW� OHW�XV�PL[

131�DQG�313�GHYLFHV�RQ�WKH�VDPH�PRGXOH��:KHQ�ZH�DUH�XVLQJ�D�VHQVRU��SKRWR�H\H�

SUR[�� HWF��� ZH� GR�� KRZHYHU�� KDYH� WR� ZRUU\� DERXW� LWV� RXWSXW� FRQILJXUDWLRQ�� $OZD\V

YHULI\� ZKHWKHU� LWV� 313� RU� 131�� �&KHFN� ZLWK� WKH� PDQXIDFWXUHU� ZKHQ� XQVXUH��� 7KH

GLIIHUHQFH�EHWZHHQ�WKH�WZR�W\SHV�LV�ZKHWKHU�WKH�ORDG��LQ�RXU�FDVH��WKH�SOF�LV�WKH�ORDG��LV

VZLWFKHG�WR�JURXQG�RU�SRVLWLYH�YROWDJH��$Q�131�W\SH�VHQVRU�KDV�WKH�ORDG�VZLWFKHG�WR

JURXQG�ZKHUHDV�D�313�GHYLFH�KDV�WKH�ORDG�VZLWFKHG�WR�SRVLWLYH�YROWDJH��%HORZ�LV�ZKDW

WKH�RXWSXWV�ORRN�OLNH�IRU�131�DQG�313�VHQVRUV�

Page 48: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

2Q�WKH�131�VHQVRU�ZH�FRQQHFW�RQH�RXWSXW�WR�WKH�SOFV�LQSXW�DQG�WKH�RWKHU�RXWSXW�WR�WKH

SRZHU�VXSSO\�JURXQG��,I�WKH�VHQVRU�LV�QRW�SRZHUHG�IURP�WKH�VDPH�VXSSO\�DV�WKH�SOF��ZH

VKRXOG�FRQQHFW�ERWK�JURXQGV�WRJHWKHU��131�VHQVRUV�DUH�PRVW�FRPPRQO\�XVHG�LQ�1RUWK

$PHULFD�DQG�-DSDQ��0DQ\�HQJLQHHUV�ZLOO�VD\�WKDW�313�LV�EHWWHU��L�H��VDIHU��EHFDXVH�WKH

ORDG�LV�VZLWFKHG�WR�JURXQG�EXW�ZKDWHYHU�ZRUNV�IRU�\RX�LV�DOZD\V�EHVW�

,QVLGH�WKH�VHQVRU��WKH�WUDQVLVWRU�LV�MXVW�DFWLQJ�DV�D�VZLWFK��7KH�VHQVRUV�LQWHUQDO�FLUFXLW

WHOOV�WKH�RXWSXW�WUDQVLVWRU�WR�WXUQ�RQ�ZKHQ�D�WDUJHW�LV�SUHVHQW��7KH�WUDQVLVWRU�WKHQ�FORVHV

WKH�FLUFXLW�EHWZHHQ�WKH���FRQQHFWLRQV�VKRZQ�DERYH���LQ�UHG�DQG�JUH\��

7KH�3/&V�GF�LQSXW�PRGXOHV�FLUFXLW�W\SLFDOO\�ORRNV�OLNH�WKLV�

7KH�RQO\� WKLQJV�DFFHVVLEOH� WR� WKH�XVHU�DUH� WKH� WHUPLQDOV� ODEHOOHG�&20021��,1387

������,1387�������,1387�[[[[����7KH�FRPPRQ�WHUPLQDO�HLWKHU�JHWV�FRQQHFWHG�WR�9�

RU�JURXQG��:KHUH�LWV�FRQQHFWHG�GHSHQGV�XSRQ�WKH�W\SH�RI�VHQVRU�XVHG��:KHQ�XVLQJ�DQ

Page 49: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

131�VHQVRU�WKLV�WHUPLQDO�LV�FRQQHFWHG�WR�9���:KHQ�XVLQJ�D�313�VHQVRU�WKLV�WHUPLQDO

LV�FRQQHFWHG�WR��9��JURXQG����$�FRPPRQ�VZLWFK��L�H��OLPLW�VZLWFK��SXVKEXWWRQ��WRJJOH�

HWF���ZRXOG� EH� FRQQHFWHG� WR� WKH� LQSXWV� LQ� D� VLPLODU� IDVKLRQ��2QH� VLGH� RI� WKH� VZLWFK

ZRXOG�EH�FRQQHFWHG�GLUHFWO\�WR�9���7KH�RWKHU�HQG�JRHV�WR�WKH�SOF�LQSXW�WHUPLQDO��7KLV

DVVXPHV� WKH� FRPPRQ� WHUPLQDO� LV� FRQQHFWHG� WR� �9� �JURXQG��� ,I� WKH� FRPPRQ� LV

FRQQHFWHG� WR�9�� WKHQ�VLPSO\�FRQQHFW�RQH�HQG�RI� WKH� VZLWFK� WR��9� �JURXQG�� DQG� WKH

RWKHU�HQG�WR�WKH�SOF�LQSXW�WHUPLQDO�

7KH�SKRWRFRXSOHUV�DUH�XVHG�WR�LVRODWH�WKH�3/&V�LQWHUQDO�FLUFXLW�IURP�WKH�LQSXWV��7KLV

HOLPLQDWHV�WKH�FKDQFH�RI�DQ\�HOHFWULFDO�QRLVH�HQWHULQJ�WKH�LQWHUQDO�FLUFXLWU\��7KH\�ZRUN

E\�FRQYHUWLQJ�WKH�HOHFWULFDO�LQSXW�VLJQDO�WR�OLJKW�DQG�WKHQ�E\�FRQYHUWLQJ�WKH�OLJKW�EDFN

WR�DQ�HOHFWULFDO�VLJQDO�WR�EH�SURFHVVHG�E\�WKH�LQWHUQDO�FLUFXLW�

$&�,QSXWVKWWS���ZZZ�SOFV�QHW�DFLQ���KWP

1RZ�WKDW�ZH�XQGHUVWDQG�KRZ�GF�LQSXWV�ZRUN��OHWV�WDNH�D�FORVH�ORRN�DW�DF�LQSXWV��$Q�DF

YROWDJH�LV�QRQ�SRODUL]HG��3XW�VLPSO\��WKLV�PHDQV�WKDW�WKHUH�LV�QR�SRVLWLYH�RU�QHJDWLYH�WR

�ZRUU\� DERXW���+RZHYHU�� DF� YROWDJH� FDQ� EH� TXLWH� GDQJHURXV� WR�ZRUN�ZLWK� LI�ZH� DUH

FDUHOHVV�� �5HPHPEHU� ZKHQ� \RX� VWXFN� WKH� NQLIH� LQ� WKH� WRDVWHU� DQG� JRW� D� VKRFN"� %H

FDUHIXO��7\SLFDOO\��DF�LQSXW�PRGXOHV�DUH�DYDLODEOH�WKDW�ZLOO�ZRUN�ZLWK��������������DQG

���� YROWV�� %H� VXUH� WR� SXUFKDVH� WKH� RQH� WKDW� ILWV� \RXU� QHHGV� EDVHG� XSRQ� WKH� LQSXW

GHYLFHV��YROWDJH��\RX�ZLOO�XVH�

28&+����XVH�FDUH��

$&� LQSXW�PRGXOHV� DUH� OHVV� FRPPRQ� WKHVH� GD\V� WKDQ� GF� LQSXW�PRGXOHV�� 7KH� UHDVRQ

EHLQJ�WKDW�WRGD\V�VHQVRUV�W\SLFDOO\�KDYH�WUDQVLVWRU�RXWSXWV��$�WUDQVLVWRU�ZLOO�QRW�ZRUN

ZLWK�DQ�DF�YROWDJH��0RVW�FRPPRQO\��WKH�DF�YROWDJH�LV�EHLQJ�VZLWFKHG�WKURXJK�D�OLPLW

VZLWFK� RU� RWKHU� VZLWFK� W\SH�� ,I� \RXU� DSSOLFDWLRQ� LV� XVLQJ� D� VHQVRU� LW� SUREDEO\� LV

RSHUDWLQJ�RQ�D�GF�YROWDJH�

Page 50: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

:H�W\SLFDOO\�FRQQHFW�DQ�DF�GHYLFH� WR�RXU� LQSXW�PRGXOH�DV� VKRZQ�DERYH��&RPPRQO\

WKH� DF� �KRW�� ZLUH� LV� FRQQHFWHG� WR� WKH� VZLWFK� ZKLOH� WKH� �QHXWUDO�� JRHV� WR� WKH� SOF

FRPPRQ��7KH�DF�JURXQG���UG�ZLUH�ZKHUH�DSSOLFDEOH��VKRXOG�EH�FRQQHFWHG�WR�WKH�IUDPH

JURXQG�WHUPLQDO�RI�WKH�SOF��QRW�VKRZQ��

$V� LV� WUXH� ZLWK� GF�� DF� FRQQHFWLRQV� DUH� W\SLFDOO\� FRORU� FRGHG� VR� WKDW� WKH� LQGLYLGXDO

ZLULQJ� WKH� GHYLFH� NQRZV� ZKLFK� ZLUH� LV� ZKLFK�� 7KLV� FRGLQJ� YDULHV� IURP� FRXQWU\� WR

FRXQWU\�EXW� LQ� WKH�86� LV� FRPPRQO\�ZKLWH� �QHXWUDO��� EODFN� �KRW�� DQG�JUHHQ� ��UG�ZLUH

JURXQG�ZKHQ�DSSOLFDEOH���2XWVLGH� WKH�86� LWV� FRPPRQO\� FRGHG� DV�EURZQ� �KRW��� EOXH

�QHXWUDO��DQG�JUHHQ�ZLWK�D�\HOORZ�VWULSH���UG�ZLUH�JURXQG�ZKHUH�DSSOLFDEOH��

7KH�3/&V�DF�LQSXW�PRGXOH�FLUFXLW�W\SLFDOO\�ORRNV�OLNH�WKLV�

7KH�RQO\� WKLQJV� DFFHVVLEOH� WR� WKH�XVHU� DUH� WKH� WHUPLQDOV� ODEHOHG�&20021�� ,1387

������,1387[[[[����7KH�FRPPRQ�WHUPLQDO�JHWV�FRQQHFWHG�WR�WKH�QHXWUDO�ZLUH�

$�FRPPRQ�VZLWFK��L�H�� OLPLW�VZLWFK��SXVKEXWWRQ�� WRJJOH��HWF���ZRXOG�EH�FRQQHFWHG� WR

WKH� LQSXW� WHUPLQDOV� GLUHFWO\��2QH� VLGH� RI� WKH� VZLWFK� ZRXOG� EH� FRQQHFWHG� GLUHFWO\� WR

,1387� ;;;�� 7KH� RWKHU� HQG� JRHV� WR� WKH� DF� KRW� ZLUH�� 7KLV� DVVXPHV� WKH� FRPPRQ

WHUPLQDO�LV�FRQQHFWHG�WR�QHXWUDO��$OZD\V�FKHFN�WKH�PDQXIDFWXUHUV�VSHFLILFDWLRQV�EHIRUH

ZLULQJ��WR�EH�VXUH�$1'�6$)(�

7KH�SKRWRFRXSOHUV�DUH�XVHG�WR� LVRODWH� WKH�3/&V�LQWHUQDO�FLUFXLW�IURP�WKH�LQSXWV��7KLV

HOLPLQDWHV�WKH�FKDQFH�RI�DQ\�HOHFWULFDO�QRLVH�HQWHULQJ�WKH�LQWHUQDO�FLUFXLWU\��7KH\�ZRUN

E\�FRQYHUWLQJ�WKH�HOHFWULFDO�LQSXW�VLJQDO�WR�OLJKW�DQG�WKHQ�E\�FRQYHUWLQJ�WKH�OLJKW�EDFN

WR�DQ�HOHFWULFDO�VLJQDO�WR�EH�SURFHVVHG�E\�WKH�LQWHUQDO�FLUFXLW�

2QH�ODVW�QRWH��W\SLFDOO\�DQ�DF�LQSXW�WDNHV�ORQJHU�WKDQ�D�GF�LQSXW�IRU�WKH�SOF�WR�VHH��,Q

PRVW�FDVHV�LW�GRHVQW�PDWWHU�WR�WKH�SURJUDPPHU�EHFDXVH�DQ�DF�LQSXW�GHYLFH�LV�W\SLFDOO\

D�PHFKDQLFDO�VZLWFK�DQG�PHFKDQLFDO�GHYLFHV�DUH�VORZZZZZZ��,WV�TXLWH�FRPPRQ�IRU

D�SOF�WR�UHTXLUH�WKDW�WKH�LQSXW�EH�RQ�IRU����RU�PRUH�PLOOLVHFRQGV�EHIRUH�LWV�VHHQ��7KLV

GHOD\� LV� UHTXLUHG�EHFDXVH�RI� WKH� ILOWHULQJ�ZKLFK� LV�QHHGHG�E\� WKH�SOF� LQWHUQDO�FLUFXLW�

5HPHPEHU�WKDW�WKH�SOF�LQWHUQDO�FLUFXLW�W\SLFDOO\�ZRUNV�ZLWK���RU�OHVV�YROWV�GF�

Page 51: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

5HOD\�2XWSXWVKWWS���ZZZ�SOFV�QHW�UHOD\RXW���KWP

%\�QRZ�ZH�VKRXOG�KDYH�D�JRRG�XQGHUVWDQGLQJ�RI�KRZ�WKH�LQSXWV�DUH�XVHG��1H[W�XS�LV

WKH�RXWSXW�FLUFXLWV�

2QH�RI�WKH�PRVW�FRPPRQ�W\SHV�RI�RXWSXWV�DYDLODEOH�LV�WKH�UHOD\�RXWSXW��$�UHOD\�FDQ�EH

XVHG� ZLWK� ERWK� $&� DQG� '&� ORDGV�� $� ORDG� LV� VLPSO\� D� IDQF\� ZRUG� IRU� ZKDWHYHU� LV

FRQQHFWHG�WR�RXU�RXWSXWV��:H�FDOO�LW�D�ORDG�EHFDXVH�ZH�DUH��ORDGLQJ�WKH�RXWSXW��ZLWK

VRPHWKLQJ�� ,I� ZH� FRQQHFWHG� QR� ORDG� WR� WKH� RXWSXW� �L�H�� MXVW� FRQQHFW� LW� GLUHFWO\� WR� D

SRZHU� VXSSO\�� ZH� ZRXOG� FHUWDLQO\� GDPDJH� WKH� RXWSXWV�� 7KLV� ZRXOG� EH� VLPLODU� WR

UHSODFLQJ�WKH�OLJKWEXOE�LQ�WKH�ODPS�\RXUH�XVLQJ�WR�UHDG�WKLV�ZLWK�D�SLHFH�RI�ZLUH��,I�\RX

GLG� WKLV�� WKH� ODPS�ZRXOG� GUDZ� D� WUHPHQGRXV� DPRXQW� RI� FXUUHQW� IURP� WKH� RXWOHW� DQG

FHUWDLQO\�SRS�\RXU�FLUFXLW�EUHDNHU�RU�EORZ�\RXU� IXVH�RU�\RXU�EUDLQV�� �7DNH�RXU�ZRUG�

3OHDVH�GRQW�WU\�LW��([WUHPHO\�GDQJHURXV��

6RPH�FRPPRQ�IRUPV�RI�D�ORDG�DUH�D�VROHQRLG��ODPS��PRWRU��HWF��7KHVH��ORDGV��FRPH�LQ

DOO�VL]HV��(OHFWULFDO�VL]HV��WKDW�LV��$OZD\V�FKHFN�WKH�VSHFLILFDWLRQV�RI�\RXU�ORDG�EHIRUH

FRQQHFWLQJ� LW� WR� WKH� SOF� RXWSXW�� <RX� DOZD\V� ZDQW� WR� PDNH� VXUH� WKDW� WKH� PD[LPXP

FXUUHQW�LW�ZLOO�FRQVXPH�LV�ZLWKLQ�WKH�VSHFLILFDWLRQV�RI�WKH�SOF�RXWSXW��,I�LW�LV�QRW�ZLWKLQ

WKH� VSHFLILFDWLRQV� �L�H�� GUDZV� WRR�PXFK� FXUUHQW�� LW�ZLOO� SUREDEO\� GDPDJH� WKH� RXWSXW�

:KHQ� LQ� GRXEW�� GRXEOH� FKHFN� ZLWK� WKH� PDQXIDFWXUHU� WR� VHH� LI� LW� FDQ� EH� FRQQHFWHG

ZLWKRXW�SRWHQWLDO�GDPDJH�

6RPH� W\SHV�RI� ORDGV�DUH�YHU\�GHFHLYLQJ��7KHVH�GHFHLYLQJ� ORDGV�DUH�FDOOHG��LQGXFWLYH

ORDGV���7KHVH�KDYH�D�WHQGHQF\�WR�GHOLYHU�D��EDFN�FXUUHQW��ZKHQ�WKH\�WXUQ�RQ��7KLV�EDFN

FXUUHQW�LV�OLNH�D�YROWDJH�VSLNH�FRPLQJ�WKURXJK�WKH�V\VWHP�

$�JRRG�H[DPSOH�RI�DQ�LQGXFWLYH�ORDG�WKDW�PRVW�RI�XV�VHH�DERXW���PRQWKV�SHU�\HDU�LV�DQ

DLU�FRQGLWLRQLQJ�XQLW��3HUKDSV�LQ�\RXU�KRPH�\RX�KDYH�DQ�DLU�FRQGLWLRQHU���XQOHVV�\RX

OLYH� LQ� WKH� DUFWLF� \RX� SUREDEO\� GR��� +DYH� \RX� HYHU� QRWLFHG� WKDW� ZKHQ� WKH� DLU

FRQGLWLRQHU� �NLFNV�RQ�� WKH� OLJKWV�GLP� IRU� D� VHFRQG�RU� WZR��7KHQ� WKH\� UHWXUQ� WR� WKHLU

QRUPDO�EULJKWQHVV��7KLV�LV�EHFDXVH�ZKHQ�WKH�DLU�FRQGLWLRQHU�WXUQV�RQ�LW�WULHV�WR�GUDZ�D

ORW� RI� FXUUHQW� WKURXJK� \RXU� ZLULQJ� V\VWHP�� $IWHU� WKLV� LQLWLDO� �NLFN�� LW� UHTXLUHV� OHVV

FXUUHQW�DQG�WKH�OLJKWV�JR�EDFN�WR�QRUPDO��7KLV�FRXOG�EH�GDQJHURXV�WR�\RXU�3/&V�RXWSXW

UHOD\V��,W�FDQ�EH�HVWLPDWHG�WKDW�WKLV�NLFN�LV�DERXW����WLPHV�WKH�UDWHG�FXUUHQW�RI�WKH�ORDG�

7\SLFDOO\�D�GLRGH��YDULVWRU��RU�RWKHU��VQXEEHU��FLUFXLW� VKRXOG�EH�XVHG� WR�KHOS�FRPEDW

DQ\�GDPDJH�WR�WKH�UHOD\��(QRXJK�VDLG��/HWV�VHH�KRZ�ZH�FDQ�XVH�WKHVH�RXWSXWV� LQ� WKH

�UHDO�SOF�ZRUOG��

Page 52: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

6KRZQ�DERYH�LV�D�W\SLFDO�PHWKRG�RI�FRQQHFWLQJ�RXU�RXWSXWV�WR�WKH�SOF�UHOD\V��$OWKRXJK

RXU�GLDJUDP�VKRZV�WKH�RXWSXW�FRQQHFWHG�WR�DQ�$&�VXSSO\��'&�FDQ�EH�XVHG�DV�ZHOO��$

UHOD\�LV�QRQ�SRODUL]HG�DQG�W\SLFDOO\�LW�FDQ�VZLWFK�HLWKHU�$&�RU�'&��+HUH�WKH�FRPPRQ

LV� FRQQHFWHG� WR� RQH� HQG� RI� RXU� SRZHU� VXSSO\� DQG� WKH� RWKHU� HQG� RI� WKH� VXSSO\� LV

FRQQHFWHG� WR� WKH� ORDG�� 7KH� RWKHU� KDOI� RI� RXU� ORDG� JHWV� FRQQHFWHG� WR� WKH� DFWXDO� SOF

RXWSXW�\RX�KDYH�GHVLJQDWHG�ZLWKLQ�\RXU�ODGGHU�SURJUDP�

7KH� UHOD\� LV� LQWHUQDO� WR� WKH� SOF�� ,WV� FLUFXLW� GLDJUDP� W\SLFDOO\� ORRNV� OLNH� WKDW� VKRZQ

DERYH��:KHQ� RXU� ODGGHU� GLDJUDP� WHOOV� WKH� RXWSXW� WR� WXUQ� RQ�� WKH� SOF� ZLOO� LQWHUQDOO\

DSSO\�D�YROWDJH�WR� WKH�UHOD\�FRLO��7KLV�YROWDJH�ZLOO�DOORZ�WKH�SURSHU�FRQWDFW� WR�FORVH�

:KHQ�WKH�FRQWDFW�FORVHV��DQ�H[WHUQDO�FXUUHQW� LV�DOORZHG� WR� IORZ�WKURXJK�RXU�H[WHUQDO

FLUFXLW��:KHQ� WKH� ODGGHU� GLDJUDP� WHOOV� WKH� SOF� WR� WXUQ� RII� WKH� RXWSXW�� LW� ZLOO� VLPSO\

UHPRYH� WKH� YROWDJH� IURP� WKH� LQWHUQDO� FLUFXLW� WKHUHE\� HQDEOLQJ� WKH� RXWSXW� FRQWDFW� WR

UHOHDVH��2XU�ORDG�ZLOO�WKDQ�KDYH�DQ�RSHQ�FLUFXLW�DQG�ZLOO�WKHUHIRUH�EH�RII��6LPSOH��LVQW

LW"

7UDQVLVWRU�2XWSXWVKWWS���ZZZ�SOFV�QHW� WUDQVRXW���KWP

7KH� QH[W� W\SH� RI� RXWSXW� ZH� VKRXOG� OHDUQ� DERXW� LV� RXU� WUDQVLVWRU� W\SH� RXWSXWV�� ,W� LV

LPSRUWDQW� WR� QRWH� WKDW� D� WUDQVLVWRU� FDQ� RQO\� VZLWFK� D� GF� FXUUHQW�� )RU� WKLV� UHDVRQ� LW

FDQQRW�EH�XVHG�ZLWK�DQ�$&�YROWDJH�

:H�FDQ�WKLQN�RI�D�WUDQVLVWRU�DV�D�VROLG�VWDWH�VZLWFK��2U�PRUH�VLPSO\�SXW��DQ�HOHFWULFDO

VZLWFK��$� VPDOO� FXUUHQW� DSSOLHG� WR� WKH� WUDQVLVWRUV� �EDVH�� �L�H�� LQSXW�� OHWV� XV� VZLWFK� D

PXFK�ODUJHU�FXUUHQW�WKURXJK�LWV�RXWSXW��7KH�SOF�DSSOLHV�D�VPDOO�FXUUHQW�WR�WKH�WUDQVLVWRU

EDVH�DQG�WKH�WUDQVLVWRU�RXWSXW��FORVHV���:KHQ�LWV�FORVHG�� WKH�GHYLFH�FRQQHFWHG�WR� WKH

SOF�RXWSXW�ZLOO�EH� WXUQHG�RQ��7KH�DERYH� LV�D�YHU\�VLPSOH�H[SODQDWLRQ�RI�D� WUDQVLVWRU�

7KHUH�DUH��RI�FRXUVH��PRUH�GHWDLOV�LQYROYHG�EXW�ZH�GRQW�QHHG�WR�JHW�WRR�GHHS�

Page 53: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

:H�VKRXOG�DOVR�NHHS�LQ�PLQG�WKDW�DV�ZH�VDZ�EHIRUH�ZLWK�WKH�LQSXW�FLUFXLWV�� WKHUH�DUH

JHQHUDOO\�PRUH� WKDQ�RQH� W\SH�RI� WUDQVLVWRU�DYDLODEOH��7\SLFDOO\�D�SOF�ZLOO�KDYH�HLWKHU

131� RU� 313� W\SH� RXWSXWV�� 7KH� �SK\VLFDO�� W\SH� RI� WUDQVLVWRU� XVHG� DOVR� YDULHV� IURP

PDQXIDFWXUHU� WR� PDQXIDFWXUHU�� 6RPH� RI� WKH� FRPPRQ� W\SHV� DYDLODEOH� DUH� %-7� DQG

026)(7��$�%-7�W\SH��%LSRODU�-XQFWLRQ�7UDQVLVWRU��RIWHQ�KDV�OHVV�VZLWFKLQJ�FDSDFLW\

�L�H��LW�FDQ�VZLWFK�OHVV�FXUUHQW��WKDQ�D�026�)(7��0HWDO�2[LGH�6HPLFRQGXFWRU��)LHOG

(IIHFW�7UDQVLVWRU��W\SH��7KH�%-7�DOVR�KDV�D�VOLJKWO\�IDVWHU�VZLWFKLQJ�WLPH��2QFH�DJDLQ�

SOHDVH�FKHFN�WKH�RXWSXW�VSHFLILFDWLRQV�RI�WKH�SDUWLFXODU�SOF�\RX�DUH�JRLQJ�WR�XVH��1HYHU

H[FHHG�WKH�PDQXIDFWXUHUV�PD[LPXP�VZLWFKLQJ�FXUUHQW�

6KRZQ�DERYH�LV�KRZ�ZH�W\SLFDOO\�FRQQHFW�RXU�RXWSXW�GHYLFH� WR� WKH� WUDQVLVWRU�RXWSXW�

3OHDVH� QRWH� WKDW� WKLV� LV� DQ�131� W\SH� WUDQVLVWRU�� ,I� LW�ZHUH� D� 313� W\SH�� WKH� FRPPRQ

WHUPLQDO�ZRXOG�PRVW� OLNHO\�EH�FRQQHFWHG�WR�9��DQG�9��ZRXOG�FRQQHFW� WR�RQH�HQG�RI

RXU� ORDG�� 1RWH� WKDW� VLQFH� WKLV� LV� D� '&� W\SH� RXWSXW� ZH� PXVW� DOZD\V� REVHUYH� SURSHU

SRODULW\� IRU� WKH� RXWSXW�� 2QH� HQG� RI� WKH� ORDG� LV� FRQQHFWHG� GLUHFWO\� WR� 9�� DV� VKRZQ

DERYH�

/HWV�WDNH�D�PRPHQW�DQG�VHH�ZKDW�KDSSHQV�LQVLGH�WKH�RXWSXW�FLUFXLW��6KRZQ�EHORZ�LV�D

W\SLFDO�RXWSXW�FLUFXLW�GLDJUDP�IRU�DQ�131�W\SH�RXWSXW�

1RWLFH�WKDW�DV�ZH�VDZ�ZLWK�WKH�WUDQVLVWRU�W\SH�LQSXWV��WKHUH�LV�D�SKRWRFRXSOHU�LVRODWLQJ

WKH� �UHDO�ZRUOG�� IURP� WKH� LQWHUQDO� FLUFXLW��:KHQ� WKH� ODGGHU� GLDJUDP� FDOOV� IRU� LW�� WKH

LQWHUQDO�FLUFXLW�WXUQV�RQ�WKH�SKRWRFRXSOHU�E\�DSSO\LQJ�D�VPDOO�YROWDJH�WR�WKH�/('�VLGH

RI� WKH� SKRWRFRXSOHU�� 7KLV� PDNHV� WKH� /('� HPLW� OLJKW� DQG� WKH� UHFHLYLQJ� SDUW� RI� WKH

SKRWRFRXSOHU�ZLOO�VHH�LW�DQG�DOORZ�FXUUHQW�WR�IORZ��7KLV�VPDOO�FXUUHQW�ZLOO�WXUQ�RQ�WKH

EDVH� RI� WKH� RXWSXW� WUDQVLVWRU� FRQQHFWHG� WR� RXWSXW� ������ 7KHUHIRUH�� ZKDWHYHU� LV

FRQQHFWHG�EHWZHHQ�&20�DQG������ZLOO� WXUQ�RQ��:KHQ� WKH� ODGGHU� WHOOV� ����� WR� WXUQ

RII�� WKH� /('� ZLOO� VWRS� HPLWWLQJ� OLJKW� DQG� KHQFH� WKH� RXWSXW� WUDQVLVWRU� FRQQHFWHG

EHWZHHQ������DQG�&20�ZLOO�WXUQ�RII�

Page 54: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

2QH�RWKHU�LPSRUWDQW�WKLQJ�WR�QRWH�LV�WKDW�D�WUDQVLVWRU�W\SLFDOO\�FDQQRW�VZLWFK�DV�ODUJH�D

ORDG�DV�D�UHOD\��&KHFN�WKH�PDQXIDFWXUHUV�VSHFLILFDWLRQV�WR�ILQG�WKH�ODUJHVW� ORDG�LW�FDQ

VDIHO\�VZLWFK��,I� WKH�ORDG�FXUUHQW�\RX�QHHG� WR�VZLWFK�H[FHHGV� WKH�VSHFLILFDWLRQ�RI� WKH

RXWSXW��\RX�FDQ�FRQQHFW�WKH�SOF�RXWSXW�WR�DQ�H[WHUQDO�UHOD\��7KHQ�FRQQHFW�WKH�UHOD\�WR

WKH�ODUJH�ORDG��<RX�PD\�EH�WKLQNLQJ���ZK\�QRW�MXVW�XVH�D�UHOD\�LQ�WKH�ILUVW�SODFH�"�7KH

DQVZHU�LV�EHFDXVH�D�UHOD\�LV�QRW�DOZD\V�WKH�FRUUHFW�FKRLFH�IRU�HYHU\�RXWSXW��$�WUDQVLVWRU

JLYHV�\RX�WKH�RSSRUWXQLW\�WR�XVH�H[WHUQDO�UHOD\V�ZKHQ�DQG�RQO\�ZKHQ�QHFHVVDU\�

,Q�VXPPDU\��D�WUDQVLVWRU�LV�IDVW��VZLWFKHV�D�VPDOO�FXUUHQW��KDV�D�ORQJ�OLIHWLPH�DQG�ZRUNV

ZLWK�GF�RQO\��:KHUHDV�D�UHOD\�LV�VORZ��FDQ�VZLWFK�D�ODUJH�FXUUHQW��KDV�D�VKRUWHU�OLIHWLPH

DQG�ZRUNV�ZLWK�DF�RU�GF��6HOHFW�WKH�DSSURSULDWH�RQH�EDVHG�XSRQ�\RXU�DFWXDO�DSSOLFDWLRQ

QHHGV�

&RPPXQLFDWLRQV�+LVWRU\KWWS���ZZZ�SOFV�QHW�FRPKLVWRU\���KWP

%\�IDU��WKH�PRVW�SRSXODU�PHWKRG�RI�FRPPXQLFDWLQJ�ZLWK�H[WHUQDO�GHYLFHV�LV�E\�XVLQJ

WKH� �56������ FRPPXQLFDWLRQV� PHWKRG�� &RPPXQLFDWLRQ� ZLWK� H[WHUQDO� GHYLFHV� LV

YLHZHG� E\� PDQ\� SOF� SURJUDPPHUV� WR� EH� GLIILFXOW� LI� QRW� �DOO� EXW� LPSRVVLEOH�� WR

XQGHUVWDQG��7KLV�LV�IDU�IURP�WUXH��,WV�QRW��EODFN�DUW����ZLWFKFUDIW��RU��ZHLUG�VFLHQFH��

5HDG�RQ���

$OO�SOF�FRPPXQLFDWLRQ�V\VWHPV�KDYH�WKHLU�URRWV�LQ�WKH�ROG�WHOHJUDSK�ZH�PD\�KDYH�VHHQ

LQ�WKH�ROG�PRYLHV���5HPHPEHU�WKH�JX\�ZRUNLQJ�DW�WKH�WUDLQ�VWDWLRQ�ZLWK�WKH�DUP�EDQG

DQG�SODVWLF�YLVRU"��(DUO\�DWWHPSWV� WR�FRPPXQLFDWH�HOHFWURQLFDOO\�RYHU� ORQJ�GLVWDQFHV

EHJDQ�DV�HDUO\�DV�WKH�ODWH�����V��,Q������D�*HUPDQ�PDQ��YRQ�6RHPPHULQJ��ZDV�XVLQJ

D�GHYLFH�ZLWK����ZLUHV����IRU�HDFK�OHWWHU�RI�WKH�DOSKDEHW��DWWDFKHG�WR�WKH�ERWWRP�RI�DQ

DTXDULXP��:KHQ�FXUUHQW�SDVVHG�WKURXJK�WKH�ZLUHV��HOHFWURO\WLF�DFWLRQ�SURGXFHG�VPDOO

EXEEOHV��%\�FKRRVLQJ�WKH�DSSURSULDWH�ZLUHV�WR�HQHUJL]H��KH�ZDV�DEOH�WR�VHQG�HQFRGHG

PHVVDJHV��YLD�EXEEOHV����,WV�WUXH���UHDOO\��7KLV�WKHQ�FDXJKW�WKH�DWWHQWLRQ�RI�WKH�PLOLWDU\

DQG�WKH�UDFH�WR�ILQG�D�V\VWHP�ZDV�RQ�

,Q���������(QJOLVKPHQ��&RRNH�DQG�:KHDWVWRQH��KDG�D����PLOH� WHOHJUDSK� LQ�XVH�E\�D

%ULWLVK� UDLOURDG�� 7KHLU� GHYLFH� KDG� �� ZLUHV� SRZHULQJ� VPDOO� HOHFWURPDJQHWV� ZKLFK

GHIOHFWHG�ORZ�PDVV�QHHGOHV��%\�DSSO\LQJ�FXUUHQW�WR�GLIIHUHQW�FRPELQDWLRQV�RI���ZLUHV

DW� D� WLPH� WKH� QHHGOHV� ZHUH� GHIOHFWHG� VR� WKDW� WKH\� SRLQWHG� WR� OHWWHUV� RI� WKH� DOSKDEHW

DUUDQJHG�LQ�D�PDWUL[��7KLV����RI����FRGH�RQO\�DOORZHG����FRPELQDWLRQV�VR�WKH�OHWWHUV

�]�Y�X�T�M�DQG�F��ZHUH�RPLWWHG��7KLV�WHOHJUDSK�ZDV�D�ELJ�VWHS�IRU�WKH�WLPH��EXW�WKH�FRGH

ZDV�QRW�ELQDU\��RQ�RII��EXW�UDWKHU�LW�ZDV�WULQDU\��WKH�QHHGOH�PRYHG�OHIW��ULJKW��RU�QRW�DW

DOO��

Page 55: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

7KH�ELJJHVW�SUREOHPV�ZLWK�WKHVH�GHYLFHV�ZDV�WKH�IDFW�WKDW�WKH\�ZHUH�SDUDOOHO��UHTXLUHG

PXOWLSOH�ZLUHV���&RRNH� DQG�:KHDWVWRQH� HYHQWXDOO\�PDGH� D� WZR�ZLUH� GHYLFH� EXW� WKH

ILUVW� SUDFWLFDO� IXOO\� VHULDO� ELQDU\� V\VWHP� JHQHUDOO\� JHWV� FUHGLWHG� WR� 6�)�%��0RUVH�� ,Q

0RUVH�FRGH��FKDUDFWHUV�DUH�V\PEROL]HG�E\�GRWV�DQG�GDVKHV�ELQDU\���V�DQG��V���0RUVHV

ILUVW�V\VWHP�LVQW�OLNH�ZH�VHH�WRGD\�LQ�WKH�PRYLHV���,WV�RQ�GLVSOD\�DW�WKH�6PLWKVRQLDQ�LQ

'&�LI�\RX�ZDQW�WR�VHH�LW��,W�DFWXDOO\�KDG�D�QHHGOH�FRQWDFWLQJ�D�URWDWLQJ�GUXP�RI�SDSHU

WKDW� PDGH� D� FRQWLQXRXV� PDUN�� %\� HQHUJL]LQJ� DQ� HOHFWURPDJQHW� WKH� QHHGOH� ZRXOG

�ERXQFH��DZD\�IURP�WKH�SDSHU�FUHDWLQJ�D�VSDFH��9HU\�VRRQ�WHOHJUDSK�RSHUDWRUV�QRWLFHG

WKDW�WKH\�GLGQW�KDYH�WR�ORRN�DW�WKH�SDSHU�WR�UHDG�WKH�FRGH�EXW�WKH\�FRXOG�LQWHUSUHW�WKH

FRGH� E\� WKH� VRXQG� WKH� QHHGOH�PDGH�ZKHQ� VFUDWFKLQJ� WKH� SDSHU�� 6R� WKLV� GHYLFH� ZDV

UHSODFHG� E\� D� VRXQGHU� WKDW� SURGXFHG� FOLFN� VRXQGV� LQVWHDG� RI� SDSHU� HWFKLQJV�

7HOHSULQWHUV� FDPH� ODWHU�� DQG� WRGD\V� VHULDO� FRPPXQLFDWLRQV� GHYLFHV� DUH�PRUH� FORVHO\

UHODWHG�WR�WKHP��7KH�UHVW�LV�KLVWRU\����H[WLQFW��EXW�KLVWRU\�DQ\ZD\�

,QFLGHQWDOO\�� WKH� WHUPV� 0$5.� DQG� 63$&(� �ZHOO� VHH� WKHP� ODWHU�� RULJLQDWHG� IURP

0RUVHV�RULJLQDO�GHYLFH��:KHQ�WKH�QHHGOH�FRQWDFWHG�WKH�SDSHU�ZH�FDOOHG�WKLV�D�0$5.

DQG� ZKHQ� WKH� QHHGOH� ERXQFHG� LW� ZDV� FDOOHG� D� 63$&(�� +LV� GHYLFH� RQO\� SURGXFHG

833(5&$6(�OHWWHUV�ZKLFK�ZDVQW�D�ELJ�SUREOHP�WKRXJK��)XUWKHU��WKH�7LWDQLF�VLQNLQJ

�VWDQGDUGL]HG��WKH�FRGH�RI��626��ZKLFK�PHDQV��6DYH�2XU�6KLS��RU�LI�\RX�ZHUH�HYHU�LQ

WKH�86�PLOLWDU\�\RX�PLJKW�NQRZ�LW�EHWWHU�DV��6 ���2Q�D�6KLQJOH��ZKLFK�ZDV�FKLSSHG

EHHI�RQ�EUHDG�

56�����&RPPXQLFDWLRQV��KDUGZDUH�KWWS���ZZZ�SOFV�QHW�GDWD���KWP

56����� FRPPXQLFDWLRQV� LV� WKH� PRVW� SRSXODU� PHWKRG� RI� SOF� WR� H[WHUQDO� GHYLFH

FRPPXQLFDWLRQV��/HWV� WDFNOH� LW�SLHFH�E\�SLHFH� WR�VHH�KRZ�VLPSOH� LW�FDQ�EH�ZKHQ�ZH

XQGHUVWDQG�LW�

56�����LV�DQ�DV\QFKURQRXV��D�PDUFKLQJ�EDQG�PXVW�EH��LQ�V\QF��ZLWK�HDFK�RWKHU�VR�WKDW

ZKHQ� RQH� VWHSV� WKH\� DOO� VWHS�� 7KH\� DUH� DV\QFKURQRXV� LQ� WKDW� WKH\� IROORZ� WKH� EDQG

OHDGHU�WR�NHHS�WKHLU�WLPLQJ��FRPPXQLFDWLRQV�PHWKRG��:H�XVH�D�ELQDU\�V\VWHP���V�DQG

�V�� WR� WUDQVPLW� RXU� GDWD� LQ� WKH� $6&,,� IRUPDW�� �$PHULFDQ� 6WDQGDUG� &RGH� IRU

,QIRUPDWLRQ�,QWHUFKDQJH��SURQRXQFHG�$66�.(<��7KLV�FRGH�WUDQVODWHV�KXPDQ�UHDGDEOH

FRGH��OHWWHUV�QXPEHUV��LQWR��FRPSXWHU�UHDGDEOH��FRGH���V�DQG��V���2XU�SOFV�VHULDO�SRUW

LV�XVHG�IRU�WUDQVPLVVLRQ�UHFHSWLRQ�RI�WKH�GDWD��,W�ZRUNV�E\�VHQGLQJ�UHFHLYLQJ�D�YROWDJH�

Page 56: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

$� SRVLWLYH� YROWDJH� LV� FDOOHG� D� 0$5.� DQG� D� QHJDWLYH� YROWDJH� LV� FDOOHG� D� 63$&(�

7\SLFDOO\��WKH�SOF�ZRUNV�ZLWK�������YROWV��7KH�YROWDJH�EHWZHHQ�������YROWV�LV�JHQHUDOO\

QRW�XVHG�DQG�LV�FRQVLGHUHG�QRLVH�

7KHUH� DUH� �� W\SHV� RI�56����� GHYLFHV��7KH� ILUVW� LV� FDOOHG� D�'7(�GHYLFH�� 7KLV�PHDQV

'DWD�7HUPLQDO�(TXLSPHQW� DQG� D� FRPPRQ� H[DPSOH� LV� D� FRPSXWHU��7KH� RWKHU� W\SH� LV

FDOOHG�D�'&(�GHYLFH��'&(�PHDQV�'DWD�&RPPXQLFDWLRQV�(TXLSPHQW� DQG� D� FRPPRQ

H[DPSOH� LV� D� PRGHP�� <RXU� SOF� PD\� EH� HLWKHU� D� '7(� RU� '&(� GHYLFH�� &KHFN� \RXU

GRFXPHQWDWLRQ�

7KH�SOF�VHULDO�SRUW�ZRUNV�E\�WXUQLQJ�VRPH�SLQV�RQ�ZKLOH�WXUQLQJ�RWKHU�RII��7KHVH�SLQV

HDFK�DUH�GHGLFDWHG�WR�D�VSHFLILF�SXUSRVH��7KH�VHULDO�SRUW�FRPHV�LQ���IODYRUV���D����SLQ

W\SH� DQG� D� ��SLQ� W\SH�� 7KH� SLQV� DQG� WKHLU� SXUSRVHV� DUH� VKRZQ� EHORZ�� �7KLV� FKDUW

DVVXPHV�\RXU�SOF�LV�D�'7(�GHYLFH�

��3,1 ���3,1 385326(

� � IUDPH�JURXQG

� � UHFHLYH�GDWD��5'�

� � WUDQVPLW�GDWD��7'�

� �� GDWD�WHUPLQDO�UHDG\��'75�

� � VLJQDO�JURXQG

� � GDWD�VHW�UHDG\��'65�

� � UHTXHVW�WR�VHQG��576�

� � FOHDU�WR�VHQG��&76�

� �� ULQJ�LQGLFDWRU��5,�� RQO\�IRU�PRGHPV

(DFK�SLQV�SXUSRVH�LQ�GHWDLO�

x� )UDPH� JURXQG� �� 7KLV� SLQ� VKRXOG� EH� LQWHUQDOO\� FRQQHFWHG� WR� WKH� FKDVVLV� RI� WKH

GHYLFH�

x� 5HFHLYH�GDWD���7KLV�SLQ�LV�ZKHUH� WKH�GDWD� IURP�WKH�H[WHUQDO�GHYLFH�HQWHUV� WKH�SOF

VHULDO�SRUW�

x� 7UDQVPLW�GDWD���7KLV�SLQ�LV�ZKHUH�WKH�GDWD�IURP�WKH�SOF�VHULDO�SRUW� OHDYHV� WKH�SOF

HQURXWH�WR�WKH�H[WHUQDO�GHYLFH�

x� 'DWD� WHUPLQDO� UHDG\���7KLV�SLQ� LV� D�PDVWHU�FRQWURO� IRU� WKH�H[WHUQDO�GHYLFH��:KHQ

WKLV�SLQ�LV���WKH�H[WHUQDO�GHYLFH�ZLOO�QRW�WUDQVPLW�RU�UHFHLYH�GDWD�

x� 6LJQDO�JURXQG���6LQFH�GDWD�LV�VHQW�DV���RU���YROWDJH�� WKLV�SLQ�LV� WKH�JURXQG�WKDW� LV

UHIHUHQFHG�

x� 'DWD�VHW�UHDG\���8VXDOO\�H[WHUQDO�GHYLFHV�KDYH� WKLV�SLQ�DV�D�SHUPDQHQW���DQG� WKH

SOF�EDVLFDOO\�XVHV�LW�WR�GHWHUPLQH�WKDW�WKH�H[WHUQDO�GHYLFH�LV�SRZHUHG�XS�DQG�UHDG\�

x� 5HTXHVW� WR� VHQG� ��7KLV� LV� SDUW� RI� KDUGZDUH� KDQGVKDNLQJ��:KHQ� WKH� SOF�ZDQWV� WR

VHQG�GDWD�WR�WKH�H[WHUQDO�GHYLFH�LW�VHWV�WKLV�SLQ�WR�D����,Q�RWKHU�ZRUGV��LW�VHWV�WKH�SLQ

WR�D���DQG�EDVLFDOO\�VD\V��,�ZDQW� WR�VHQG�\RX�GDWD��,V� LW�RN"��7KH�H[WHUQDO�GHYLFH

VD\V�LWV�2.�WR�VHQG�GDWD�E\�VHWWLQJ�LWV�FOHDU�WR�VHQG�SLQ�WR����7KH�SOF�WKHQ�VHQGV�WKH

GDWD�

x� &OHDU�WR�VHQG���7KLV�LV�WKH�RWKHU�KDOI�RI�KDUGZDUH�KDQGVKDNLQJ��$V�QRWHG�DERYH��WKH

H[WHUQDO�GHYLFH�VHWV�WKLV�SLQ�WR���ZKHQ�LW�LV�UHDG\�WR�UHFHLYH�GDWD�IURP�WKH�SOF�

Page 57: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

x� 5LQJ�LQGLFDWRU���RQO\�XVHG�ZKHQ�WKH�SOF�LV�FRQQHFWHG�WR�D�PRGHP�

:KDW� KDSSHQV� ZKHQ� \RXU� SOF� DQG� H[WHUQDO� GHYLFH� DUH� ERWK� '7(� �RU� ERWK� '&(�

GHYLFHV"�7KH\�FDQW�WDON�WR�HDFK�RWKHU��WKDWV�ZKDW�KDSSHQV��7KH�SLFWXUH�EHORZ�VKRZV

ZK\���VDPH�W\SH�GHYLFHV�FDQW�FRPPXQLFDWH�ZLWK�HDFK�RWKHU�

�1RWLFH� WKDW� LQ� WKH� SLFWXUH� DERYH�� WKH� UHFHLYH� GDWD� OLQH� �SLQ��� RI� WKH� ILUVW� GHYLFH� LV

FRQQHFWHG� WR� WKH� UHFHLYH� GDWD� OLQH� RI� WKH� VHFRQG� GHYLFH��$QG� WKH� WUDQVPLW� GDWD� OLQH

�SLQ���RI�WKH�ILUVW�GHYLFH�LV�FRQQHFWHG�WR�WKH�WUDQVPLW�GDWD�RI�WKH�VHFRQG�GHYLFH��,WV�OLNH

WDONLQJ�WKURXJK�D�SKRQH�ZLWK�WKH�ZLUHV�UHYHUVHG�� �L�H��\RXU�PRXWK�SLHFH� LV�FRQQHFWHG

GLUHFWO\�WR�WKH�RWKHU�SDUWLHV�PRXWKSLHFH�DQG�\RXU�HDU�SLHFH�LV�FRQQHFWHG�GLUHFWO\�WR�WKH

RWKHU�SDUWLHV�HDUSLHFH���2EYLRXVO\��WKLV�ZRQW�ZRUN�ZHOO�

�7KH� VROXWLRQ� LV� WR� XVH� D� QXOO�PRGHP� FRQQHFWLRQ� DV� VKRZQ� EHORZ�� 7KLV� LV� W\SLFDOO\

GRQH�E\�XVLQJ�D�UHYHUVH��QXOO�PRGHP��FDEOH�WR�FRQQHFW�WKH�GHYLFHV�

7R�VXPPDUL]H�HYHU\WKLQJ��KHUHV�D� W\SLFDO�FRPPXQLFDWLRQV�VHVVLRQ��%RWK�GHYLFHV�DUH

SRZHUHG�XS��7KH�SOF�LV�'7(�DQG�WKH�H[WHUQDO�GHYLFH�LV�'&(��7KH�H[WHUQDO�GHYLFH�WXUQV

RQ�'65�ZKLFK�WHOOV�WKH�SOF�WKDWV�LWV�SRZHUHG�XS�DQG��WKHUH���7KH�3/&�WXUQV�RQ�576

ZKLFK� LV� OLNH� DVNLQJ� WKH� H[WHUQDO� GHYLFH� �DUH� \RX� UHDG\� WR� UHFHLYH� VRPH� GDWD"�� 7KH

H[WHUQDO�GHYLFH�UHVSRQGV�E\�WXUQLQJ�RQ�LWV�&76�ZKLFK�VD\V�LWV�RN�WR�IRU�WKH�SOF�WR�VHQG

GDWD��7KH�SOF�VHQGV�WKH�GDWD�RQ�LWV�7'�WHUPLQDO�DQG�WKH�H[WHUQDO�GHYLFH�UHFHLYHV�LW�RQ

LWV�5'� WHUPLQDO�� 6RPH� GDWD� LV� VHQW� DQG� UHFHLYHG��$IWHU� D�ZKLOH�� WKH� H[WHUQDO� GHYLFH

FDQW� SURFHVV� WKH� GDWD� TXLFN� HQRXJK�� 6R�� LW� WXUQV� RII� LWV� &76� WHUPLQDO� DQG� WKH� SOF

SDXVHV�VHQGLQJ�GDWD��7KH�H[WHUQDO�GHYLFH�FDWFKHV�XS�DQG� WKHQ� WXUQV� LWV�&76�WHUPLQDO

EDFN�RQ��7KH�SOF�DJDLQ�VWDUWV�VHQGLQJ�GDWD�RQ�LWV�7'�WHUPLQDO�DQG�WKH�H[WHUQDO�GHYLFH

UHFHLYHV�LW�RQ�LWV�5'�WHUPLQDO��7KH�SOF�UXQV�RXW�RI�GDWD�WR�VHQG�DQG�WXUQV�RII�LWV�576

WHUPLQDO��7KH�H[WHUQDO�GHYLFH�VLWV�DQG�ZDLWV�IRU�PRUH�GDWD�

56�����&RPPXQLFDWLRQV��VRIWZDUH�KWWS���ZZZ�SOFV�QHW�������KWP

1RZ� WKDW� ZH� XQGHUVWDQG� WKH� KDUGZDUH� SDUW� RI� WKH� SLFWXUH�� OHWV� GLYH� ULJKW� LQWR� WKH

VRIWZDUH� SDUW��:HOO� WDNH� D� ORRN� DW� HDFK� SDUW� RI� WKH� SX]]OH� E\� GHILQLQJ� D� IHZ�RI� WKH

FRPPRQ� WHUPV�� (YHU�ZRQGHUHG�ZKDW� SKUDVHV� OLNH� �������1���PHDQW"� � 'R� \RX� XVH

VRIWZDUH�KDQGVKDNLQJ� RU� KDUGZDUH�KDQGVKDNLQJ� DW� IRUPDO� SDUWLHV� IRU� D� JUHHWLQJ"� ,I

\RXUH�QRW�VXUH��UHDG�RQ�

Page 58: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

$6&,,� LV� D� KXPDQ�UHDGDEOH� WR� FRPSXWHU�UHDGDEOH� WUDQVODWLRQ� FRGH�� �L�H�� HDFK

OHWWHU�QXPEHU�����LV�WUDQVODWHG�WR��V�DQG��V��,WV�D���ELW��D�ELW�LV�D���RU�D����FRGH��VR�ZH

FDQ�WUDQVODWH�����FKDUDFWHUV�� ��A�� LV������&KDUDFWHU�VHWV� WKDW�XVH� WKH��WK�ELW�GR�H[LVW

EXW� WKH\�DUH�QRW� WUXH�$6&,,��%HORZ�LV�DQ�$6&,,�FKDUW� VKRZLQJ� LWV� �KXPDQ�UHDGDEOH�

UHSUHVHQWDWLRQ��:H�W\SLFDOO\�UHIHU�WR�WKH�FKDUDFWHUV�E\�XVLQJ�KH[DGHFLPDO�WHUPLQRORJ\�

����LV���K������LV���K���(��LV���K��HWF���WKH��K��VLPSOH�PHDQV�KH[DGHFLPDO�

PRVW�VLJQLILFDQW�ELWV

� � � � � � � �

� VSDFH � # 3 C S

� ;21 � � $ 4 D T

� 67; � � % 5 E U

� (7; ;2)) � � & 6 F V

� � � ' 7 G W

� 1$. � � ( 8 H X

� $&. � ) 9 I Y

� � * : J Z

� � � + ; K [

� � � , < L \

$ /) � - = M ]

% � � . > N ^

& � � / ? O _

' &5 � 0 @ P `

( � ! 1 A Q a

/HDVW�VLJ��ELWV

) � " 2 B R

x� 6WDUW� ELW�� ,Q� 56����� WKH� ILUVW� WKLQJ� ZH� VHQG� LV� FDOOHG� D� VWDUW� ELW�� 7KLV� VWDUW� ELW

��LQYHQWHG��GXULQJ�::��E\�.OHLQVFKPLGW��LV�D�V\QFKURQL]LQJ�ELW�DGGHG�MXVW�EHIRUH

HDFK�FKDUDFWHU�ZH�DUH�VHQGLQJ��7KLV�LV�FRQVLGHUHG�D�63$&(�RU�QHJDWLYH�YROWDJH�RU

D���

x� 6WRS�ELW��7KH�ODVW�WKLQJ�ZH�VHQG�LV�FDOOHG�D�VWRS�ELW��7KLV�VWRS�ELW�WHOOV�XV�WKDW�WKH

ODVW� FKDUDFWHU� ZDV� MXVW� VHQW�� 7KLQN� RI� LW� DV� DQ� HQG�RI� �FKDUDFWHU� ELW�� 7KLV� LV

FRQVLGHUHG� D� 0$5.� RU� SRVLWLYH� YROWDJH� RU� D� ��� 7KH� VWDUW� DQG� VWRS� ELWV� DUH

FRPPRQO\�FDOOHG�IUDPLQJ�ELWV�EHFDXVH�WKH\�VXUURXQG�WKH�FKDUDFWHU�ZH�DUH�VHQGLQJ�

x� 3DULW\�ELW��6LQFH�PRVW�SOFV�H[WHUQDO�HTXLSPHQW�DUH�E\WH�RULHQWHG� ���ELWV �E\WH�� LW

VHHPV�QDWXUDO�WR�KDQGOH�GDWD�DV�D�E\WH��$OWKRXJK�$6&,,�LV�D���ELW�FRGH�LW�LV�UDUHO\

WUDQVPLWWHG� WKDW� ZD\�� 7\SLFDOO\�� WKH� �WK� ELW� LV� XVHG� DV� D� SDULW\� ELW� IRU� HUURU

FKHFNLQJ�� 7KLV� PHWKRG� RI� HUURU� FKHFNLQJ� JHWV� LWV� QDPH� IURP� WKH� PDWK� LGHD� RI

SDULW\���UHPHPEHU�WKH�RGG�HYHQ�SURSHUW\�RI� LQWHJHUV"�,�GLGQW� WKLQN�VR���,Q�VLPSOH

WHUPV��SDULW\�PHDQV�WKDW�DOO�FKDUDFWHUV�ZLOO�HLWKHU�KDYH�DQ�RGG�QXPEHU�RI��V�RU�DQ

HYHQ�QXPEHU�RI��V�� �&RPPRQ� IRUPV�RI�SDULW\� DUH�1RQH��(YHQ�� DQG�2GG�� �0DUN

DQG�6SDFH�DUHQW�YHU\�FRPPRQ�VR�,�ZRQW�GLVFXVV�WKHP���&RQVLGHU�WKHVH�H[DPSOHV�

VHQG��(�����K�RU��������E�LQDU\����,Q�SDULW\�RI�1RQH��WKH�SDULW\�ELW�LV�DOZD\V���VR

Page 59: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

ZH�VHQG�����������,Q�SDULW\�RI�(YHQ�ZH�PXVW�KDYH�DQ�(YHQ�QXPEHU�RI��V�LQ�RXU

WRWDO�FKDUDFWHU�VR�WKH�RULJLQDO�FKDUDFWHU�FXUUHQWO\�KDV����V�����������WKHUHIRUH�RXU

SDULW\�ELW�ZH�ZLOO�DGG�PXVW�EH�D���������������1RZ�ZH�KDYH�DQ�HYHQ�QXPEHU�RI

�V�� � ,Q� 2GG� SDULW\� ZH� QHHG� DQ� RGG� QXPEHU� RI� �V�� 6LQFH� RXU� RULJLQDO� FKDUDFWHU

DOUHDG\�KDV�DQ�RGG�QXPEHU�RI��V����LV�DQ�RGG�QXPEHU��ULJKW"��RXU�SDULW\�ELW�ZLOO�EH

D���������������'XULQJ�WUDQVPLVVLRQ��WKH�VHQGHU�FDOFXODWHV�WKH�SDULW\�ELW�DQG�VHQGV

LW��7KH�UHFHLYHU�FDOFXODWHV�SDULW\�IRU�WKH���ELW�FKDUDFWHU�DQG�FRPSDUHV�WKH�UHVXOW�WR

WKH�SDULW\�ELW� UHFHLYHG�� ,I� WKH�FDOFXODWHG�DQG�UHDO�SDULW\�ELWV�GRQW�PDWFK��DQ�HUURU

RFFXUUHG�DQ�ZH�DFW�DSSURSULDWHO\���,WV�VWUDQJH�WKDW�WKLV�SDULW\�PHWKRG�LV�VR�SRSXODU�

7KH�UHDVRQ�LV�EHFDXVH�LWV�RQO\�HIIHFWLYH�KDOI�WKH�WLPH��7KDW�LV��SDULW\�FKHFNLQJ�FDQ

RQO\�ILQG�HUURUV�WKDW�HIIHFW�DQ�RGG�QXPEHU�RI�ELWV��,I�WKH�HUURU�DIIHFWHG���RU���RU��

ELWV� WKH�PHWKRG� LV�XVHOHVV��7\SLFDOO\�� HUURUV�DUH�FDXVHG�E\�QRLVH�ZKLFK� FRPHV� LQ

EXUVWV� DQG� UDUHO\� HIIHFWV� �� ELW�� %ORFN� UHGXQGDQF\� FKHFNV� DUH� XVHG� LQ� RWKHU

FRPPXQLFDWLRQ�PHWKRGV�WR�SUHYHQW�WKLV�

x� %DXG� UDWH�� ,OO� SHUSHWXDWH� WKH� LQFRUUHFW� PHDQLQJ� VLQFH� LWV� PRVW� FRPPRQO\� XVHG

LQFRUUHFWO\��7KLQN�RI�EDXG�UDWH�DV� UHIHUULQJ� WR� WKH�QXPEHU�RI�ELWV�SHU�VHFRQG� WKDW

DUH� EHLQJ� WUDQVPLWWHG�� 6R� �����PHDQV� ����� ELWV� SHU� VHFRQG� DUH� EHLQJ� VHQW� DQG

����� PHDQV� ����� ELWV� DUH� EHLQJ� WUDQVPLWWHG� HYHU\� VHFRQG�� &RPPRQ� YDOXHV

�VSHHGV�� DUH� ������ ������ ������ ������ ������� DQG� ������� � 56���� GDWD� IRUPDW�

�EDXG� UDWH�GDWD� ELWV�SDULW\�VWRS� ELWV�� 7KLV� LV� WKH�ZD\� WKH� GDWD� IRUPDW� LV� W\SLFDOO\

VSHFLILHG��)RU�H[DPSOH���������1���PHDQV�D�EDXG�UDWH�RI���������GDWD�ELWV��SDULW\

RI�1RQH��DQG���VWRS�ELW�

7KH�SLFWXUH�EHORZ�VKRZV�KRZ�GDWD�OHDYHV�WKH�VHULDO�SRUW�IRU�WKH�FKDUDFWHU��(�����K����

����E��DQG�(YHQ�SDULW\�

$QRWKHU�LPSRUWDQW�WKLQJ�WKDW�LV�VRPHWLPHV�XVHG�LV�FDOOHG�VRIWZDUH�KDQGVKDNLQJ��IORZ

FRQWURO��� /LNH� WKH� KDUGZDUH� KDQGVKDNLQJ� ZH� VDZ� LQ� WKH� SUHYLRXV� FKDSWHU�� VRIWZDUH

KDQGVKDNLQJ� LV� XVHG� WR�PDNH� VXUH� ERWK� GHYLFHV� DUH� UHDG\� WR� VHQG�UHFHLYH� GDWD�� 7KH

PRVW� SRSXODU� �FKDUDFWHU� IORZ� FRQWURO�� LV� FDOOHG� ;21�;2))�� ,WV� YHU\� VLPSOH� WR

XQGHUVWDQG�� 6LPSO\� SXW�� WKH� UHFHLYHU� VHQGV� WKH� ;2))� FKDUDFWHU� ZKHQ� LW� ZDQWV� WKH

WUDQVPLWWHU� WR�SDXVH�VHQGLQJ�GDWD��:KHQ� LWV� UHDG\� WR� UHFHLYH�GDWD�DJDLQ�� LW� VHQGV� WKH

WUDQVPLWWHU�WKH�;21�FKDUDFWHU��;2))�LV�VRPHWLPHV�UHIHUUHG�WR�DV�WKH�KROGRII�FKDUDFWHU

DQG�;21�DV�WKH�UHOHDVH�FKDUDFWHU�

7KH�ODVW�WKLQJ�ZH�VKRXOG�NQRZ�DERXW�LV�GHOLPLWHUV��$�GHOLPLWHU�LV�VLPSO\�DGGHG�WR�WKH

HQG� RI� D�PHVVDJH� WR� WHOO� WKH� UHFHLYHU� WR� SURFHVV� WKH� GDWD� LW� KDV� UHFHLYHG�� 7KH�PRVW

FRPPRQ� LV� WKH�&5�RU� WKH�&5� DQG�/)�SDLU��7KH�&5� �FDUULDJH� UHWXUQ�� LV� OLNH� WKH� ROG

W\SHZULWHUV�� �UHPHPEHU� WKHP""��:KHQ�\RX�UHDFKHG� WKH�HQG�RI�D� OLQH�ZKLOH� W\SLQJ��D

EHOO�ZRXOG�VRXQG��<RX�ZRXOG�WKHQ�JUDE�WKH�KDQGOH�DQG�PRYH�WKH�FDUULDJH�EDFN�WR�WKH

VWDUW��,Q�RWKHU�ZRUGV��\RX�UHWXUQHG�WKH�FDUULDJH�WR�WKH�EHJLQQLQJ���7KLV�LV�WKH�VDPH�DV

Page 60: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

ZKDW� D�&5�GHOLPLWHU�ZLOO� GR� LI� \RX� YLHZ� LW� RQ� D� FRPSXWHU� VFUHHQ���7KH� SOF�H[WHUQDO

GHYLFH� UHFHLYHV� WKLV� DQG� NQRZV� WR� WDNH� WKH� GDWD� IURP� LWV� EXIIHU�� �ZKHUH� WKH� GDWD� LV

VWRUHG� WHPSRUDULO\�EHIRUH�EHLQJ�SURFHVVHG��$Q�/)��OLQH� IHHG�� LV� DOVR� VRPHWLPHV� VHQW

ZLWK� WKH� &5� FKDUDFWHU�� ,I� YLHZHG� RQ� D� FRPSXWHU� VFUHHQ� WKLV� ZRXOG� ORRN� OLNH� ZKDW

KDSSHQV�RQ�WKH�W\SHZULWHU�ZKHQ�WKH�FDUULDJH�LV�UHWXUQHG�DQG� WKH�SDJH�PRYHV�GRZQ�D

OLQH�VR�\RX�GRQW�W\SH�RYHU�ZKDW�\RX�MXVW�W\SHG�

6RPHWLPHV�DQ�67;�DQG�(7;�SDLU� LV�XVHG�IRU� WUDQVPLVVLRQ�UHFHSWLRQ�DV�ZHOO��67;�LV

�VWDUW�RI�WH[W��DQG�(7;�LV��HQG�RI�WH[W���7KH�67;�LV�VHQW�EHIRUH�WKH�GDWD�DQG�WHOOV�WKH

H[WHUQDO�GHYLFH�WKDW�GDWD�LV�FRPLQJ��$IWHU�DOO�WKH�GDWD�KDV�EHHQ�VHQW��DQ�(7;�FKDUDFWHU

LV�VHQW�

)LQDOO\�� ZH� PLJKW� DOVR� FRPH� DFURVV� DQ� $&.�1$.� SDLU�� 7KLV� LV� UDUHO\� XVHG� EXW� LW

VKRXOG�EH�QRWHG�DV�ZHOO��(VVHQWLDOO\��WKH�WUDQVPLWWHU�VHQGV�LWV�GDWD��,I�WKH�UHFHLYHU�JHWV

LW�ZLWKRXW� HUURU�� LW� VHQGV�EDFN� DQ�$&.�FKDUDFWHU�� ,I� WKHUH�ZDV� DQ� HUURU�� WKH� UHFHLYHU

VHQGV�EDFN�D�1$.�FKDUDFWHU�DQG�WKH�WUDQVPLWWHU�UHVHQGV�WKH�GDWD�

56�����KDV�D�ORW�RI�LQIRUPDWLRQ�WR�DEVRUE��VR�IHHO�IUHH�WR�UHUHDG�LW��,WV�QRW�VR�GLIILFXOW

LI� \RX� WDNH� \RXU� WLPH� DQG� WKLQN� DERXW� HDFK� VWHS��2WKHU� FRPPXQLFDWLRQ�PHWKRGV� JHW

HDVLHU�

8VLQJ�56�����ZLWK�/DGGHU�/RJLFKWWS���ZZZ�SOFV�QHW�UV���ODG�KWP

1RZ�WKDW�ZH�XQGHUVWDQG�ZKDW�56�����LV�PHDQV�OHWV�VHH�KRZ�WR�XVH�LW�ZLWK�RXU�SOF��:H

VKRXOG�VWDUW�RXW�DV�DOZD\V��UHPHPEHULQJ�WKDW�D�SOF� LV�D�SOF� LV�D�SOF���� ,Q�RWKHU�ZRUGV�

XQGHUVWDQG�WKH�WKHRU\�ILUVW�DQG�WKHQ�ILJXUH�RXW�KRZ�RXU�PDQXIDFWXUHU�RI�FKRLFH��PDNHV

LW�ZRUN���6RPH�PDQXIDFWXUHUV�LQFOXGH�56�����FRPPXQLFDWLRQ�FDSDELOLW\� LQ� WKH�PDLQ

SURFHVVRU��6RPH�XVH�WKH��SURJUDPPLQJ�SRUW��IRU�WKLV��2WKHUV�UHTXLUH�\RX�WR�SXUFKDVH

�L�H��VSHQG�H[WUD��V��D�PRGXOH�WR��WDON�56������ZLWK�DQ�H[WHUQDO�GHYLFH���:KDW� LV�DQ

H[WHUQDO�GHYLFH��\RX�PD\EH�DVNLQJ"�7KH�DQVZHU�LV�GLIILFXOW�EHFDXVH�WKHUH�DUH�VR�PDQ\

H[WHUQDO� GHYLFHV�� ,W� PD\� EH� DQ� RSHUDWRU� LQWHUIDFH�� DQ� H[WHUQDO� FRPSXWHU�� D� PRWRU

FRQWUROOHU��D�URERW��D�YLVLRQ�V\VWHP��D�����JHW�WKH�SRLQW""

7R� FRPPXQLFDWH� YLD� 56����� ZH� KDYH� WR� VHWXS� D� IHZ� WKLQJV�� $VN� \RXUVHOI� WKH

IROORZLQJ�TXHVWLRQV�

:KHUH��LQ�GDWD�PHPRU\��ZLOO�ZH�VWRUH�WKH�GDWD�WR�EH�VHQW"�(VVHQWLDOO\�ZH�KDYH�WR�VWRUH

WKH�GDWD�ZH�ZLOO� VHQG���� VRPHZKHUH��:KHUH� HOVH�EXW� LQ�RXU�GDWD�PHPRU\��:KHUH�� LQ

GDWD�PHPRU\��ZLOO�ZH�SXW�WKH�GDWD�ZH�UHFHLYH�IURP�WKH�H[WHUQDO�GHYLFH"�+RZ�ZLOO�ZH

WHOO�WKH�SOF�ZKHQ�LWV�WLPH�WR�VHQG�RXU�GDWD��WKH�GDWD�ZH�VWRUHG�LQ�GDWD�����PHPRU\��RXW

WKH�VHULDO�SRUW"������+RZ�ZLOO�ZH�NQRZ�ZKHQ�ZH�KDYH�UHFHLYHG�GDWD�IURP�RXU�H[WHUQDO

GHYLFH"

,I�\RX�NQRZ�WKH�DERYH��WKHQ�WKH�UHVW�LV�HDV\��,I�\RX�GRQW�NQRZ�WKH�DERYH��WKHQ�PDNH

VRPHWKLQJ�XS�DQG�QRZ�WKH�UHVW�LV�HDV\��+XK"""�6LPSOH��SLFN�D�PHPRU\�DUHD�WR�ZRUN

Page 61: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3/& 78725 ���� 3DJH ��

ZLWK�DQG�ILJXUH�RXW�LI�ZH�FDQ�FKRRVH�WKH�LQWHUQDO�UHOD\V�WR�XVH�WR�VHQG�DQG�UHFHLYH�GDWD

RU�LI�WKH�SOF�KDV�RQHV�WKDW�DUH�GHGLFDWHG�WR�WKLV�SXUSRVH��6RXQGV�WRR�VLPSOH""��1R�ZD\�

LW�LV�VLPSOH���

%HIRUH�ZH�GR� LW�� OHWV�JHW� VRPH�PRUH� WHFKQLFDO� WHUPV�RXW�RI� WKH�ZD\�VR�ZHUH�RQ� WKH

VDPH�SOD\LQJ�ILHOG�

x� %XIIHU� �� $� EXIIHU� LV� D� IDQF\� WHFKQLFDO� ZRUG� WKDW� PHDQV� D� SODVWLF� EDJ�� ,Q� RWKHU

ZRUGV��LWV�D�WHPSRUDU\�VWRUDJH�ORFDWLRQ�ZKHUH�WKH�SOF�RU�H[WHUQDO�GHYLFH�VWRUHV�GDWD

LW�KDV�UHFHLYHG��RU�LV�ZDLWLQJ�WR�VHQG��YLD�56������:KHQ�,�JR�WR�WKH�VXSHUPDUNHW�WR

EX\�P\�IDYRULWH�WY�GLQQHUV��,�FDUU\�WKHP�KRPH�LQ�D�SODVWLF�EDJ��7KH�SODVWLF�EDJ�LV

QRW� D� SHUPDQHQW� SODFH� IRU� P\� IRRG� �DUH� WY� GLQQHUV� UHDOO\� IRRG""�� EXW� UDWKHU� D

WHPSRUDU\�VWRUDJH�SODFH�IRU�WKHP�XQWLO�,�JHW�����KRPH��:KHQ�,�JHW�KRPH��,�WDNH�WKHP

RXW�RI�WKH�EDJ�DQG�FRRN�WKHP��7KH�VXSHUPDUNHW�ZDV�WKH�H[WHUQDO�GHYLFH�ZKHUH�,�JRW

WKH�GDWD��WY�GLQQHUV��IURP�DQG�P\�PLFURZDYH� LV� WKH�SOF��7KH�SODVWLF�EDJ�ZDV� WKH

EXIIHU��WHPSRUDU\�VWRUDJH�SODFH��WKDW�ZDV�KROGLQJ�P\�GDWD��WY�GLQQHU��XQWLO�,�WRRN

WKHP�RXW�WR�XVH��L�H�FRRN��

x� 6WULQJ���$�VWULQJ�LV�D�FRRO�ZD\�RI�VD\LQJ��D�EXQFK�RI�FKDUDFWHUV���7KH�ZRUG��KHOOR�

LV�D�� � � �VWULQJ��,WV�D�EXQFK�RI�FKDUDFWHUV��L�H��K�H�O�O�R��WKDW�DUH�FRQQHFWHG��VWUXQJ�

WRJHWKHU�WR�����PHDQ�VRPHWKLQJ�XVHIXO����������LV�DOVR�D�VWULQJ��$OWKRXJK�LW�PDNHV

QR�VHQVH�WR�XV��LW�PD\�PHDQ�VRPHWKLQJ�YDOXDEOH�WR�\RXU�SOF�RU�H[WHUQDO�GHYLFH��,W

FRXOG�EH�D�FRPPDQG�WKDW�WHOOV�\RXU�URERW�WR�VHQG�RXW�LWV�FXUUHQW�FRRUGLQDWHV���RU�LW

FRXOG�VLPSO\�EH�WKH�ZRUG��KHOOR��XSVLGH�GRZQ�

x� &RQFDWHQDWH���7KLV�ZRUG�LV�D�PRXWKIXOO��6LPSO\�SXW��LW�PHDQV�WR�FRPELQH���VWULQJV

WRJHWKHU� WR�PDNH� RQH� VWULQJ��$Q� H[DPSOH� LV� FRPELQLQJ� WKH� �� VWULQJV� �ODVHU�� DQG

�MHW��WRJHWKHU�WR�PDNH�RQH�VWULQJ�����ODVHUMHW��

:LWK� WKH� PXPER�MXPER� RXW� RI� WKH� ZD\� OHWV� VHH� LW� LQ� DFWLRQ�� $JDLQ�� WKH� PHPRU\

ORFDWLRQV�DQG�UHOD\V�YDU\�E\�PDQXIDFWXUHU�EXW�WKH�WKHRU\�LV�XQLYHUVDO�

��:H�DVVLJQ�PHPRU\�ORFDWLRQV�'0����WKURXJK�'0����WR�EH�ZKHUH�ZHOO�SXW�RXU�GDWD

EHIRUH�ZH�VHQG�LW�RXW�WKH�VHULDO�SRUW��1RWH��0DQ\�SOFV�KDYH�GHGLFDWHG�DUHDV�RI�PHPRU\

IRU�WKLV�DQG�RQO\�WKLV�SXUSRVH�

��:HOO�DVVLJQ�LQWHUQDO�UHOD\������WR�EH�RXU�VHQG�UHOD\��,Q�RWKHU�ZRUGV��ZKHQ�ZH�WXUQ

RQ������WKH�SOF�ZLOO�VHQG�WKH�GDWD�LQ�'0����'0����RXW�WKH�VHULDO�SRUW�WR�RXU�H[WHUQDO

GHYLFH���1RWH�DJDLQ���0DQ\�SOFV�KDYH�GHGLFDWHG�UHOD\V��VSHFLDO�XWLOLW\�UHOD\V��IRU� WKLV

DQG�RQO\�WKLVSXUSRVH��,WV�JUHDW�ZKHQ�WKH�PDQXIDFWXUHU�PDNHV�RXU�OLIH�HDV\�

:HOO� VHQG� WKH� VWULQJ� �DOU�� RXW� WKH� SOF� VHULDO� SRUW� WR� DQ� RSHUDWRU� LQWHUIDFH�ZKHQ� RXU

WHPS� VHQVRU� LQSXW� WXUQV� RQ�� 7KLV� PHDQV� RXU� RYHQ� KDV� EHFRPH� WRR� KRW�� :KHQ� WKH

RSHUDWRU� LQWHUIDFH� UHFHLYHV� WKLV� VWULQJ� LW� ZLOO� GLVSOD\HG� DQ� DODUP� PHVVDJH� IRU� WKH

RSHUDWRU�WR�VHH��/RRN�EDFN�RQ�WKH�$6&,,�FKDUW�DQG�\RXOO�VHH�WKDW��DOU��LV�KH[DGHFLPDO

���� �&�� ���� �D ���� O �&�� U ����:HOO� ZULWH� WKHVH�$6&,,� FKDUDFWHUV� �LQ� KH[DGHFLPDO

Page 62: KWWS˛ ZZZ SOFV QHW - UPpaginas.fe.up.pt/~asousa/sind/acetat/PLC_tutor__plcsnet.pdf · 56 &rpp kdugz duh 56 &rpp vriwz duh 8vlqj56 /dgghu’ldjudp bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB3DJH �� ���� 3/& 78725

IRUP�� LQWR� WKH� LQGLYLGXDO� GDWD� PHPRU\� ORFDWLRQV�� :HOO� XVH� '0��������� +RZ"

5HPHPEHU�WKH�/'$�RU�029�LQVWUXFWLRQ"�:HOO� WXUQ�RQ�RXU�VHQG�UHOD\��������ZKHQ

RXU�WHPSHUDWXUH�VHQVRU��������WXUQV�RQ��7KH�ODGGHU�LV�VKRZQ�EHORZ�

6RPH�SOFV�PD\�QRW�KDYH�GHGLFDWHG� LQWHUQDO� UHOD\V� WKDW�VHQG�RXW�RXU�GDWD� WKURXJK� WKH

56�����SRUW��:H�PD\�KDYH� WR�DVVLJQ� WKHP�PDQXDOO\��)XUWKHU�� VRPH�SOFV�ZLOO�KDYH�D

VSHFLDO�LQVWUXFWLRQ�WR�WHOO�XV�ZKHUH�WKH�GDWD�LV�VWRUHG�DQG�ZKHQ�WR�VHQG�WKH�GDWD��7KLV

LQVWUXFWLRQ�LV�FRPPRQO\�FDOOHG�$:7��$6&,,�:ULWH��RU�56��7KH�WKHRU\�LV�DOZD\V�WKH

VDPH�WKRXJK��3XW�WKH�GDWD�LQ�D�PHPRU\�ORFDWLRQ�DQG�WKHQ�WXUQ�RQ�D�UHOD\�WR�VHQG�WKH

GDWD�