CHAPTER 1 — PROGRAMMABLE LOGIC CONTROLLERS:
AN OVERVIEW
1.nWhatnisnthenprimarynfunctionnofnanProgrammablenLogicnControllern(PLC)?
A.nTonreplacenallnelectricalnwiringninnanfactory
B.nTonperformnonlynmathematicalncalculations
C.nTonmonitorninputsnandncontrolnoutputsnaccordingntonanstorednprogram
D.nTonsupplynelectricalnpowerntonmachines
✔nCORRECTnANSWER:nC
EXPERTnRATIONALE:nAnPLCnmonitorsninputndevices,nexecutesnanstoredncontrolnprogramnandnupdat
esnoutputndevicesnaccordingntonthenprogrammednlogic.nItnisnwidelynusedninnindustrialnautomation.
2.nWhichnindustryncommonlynusesnPLCs?
A.nIndustrialnmanufacturing
B.nFashionndesignnonly
C.nGraphicnillustration
D.nMusicnproduction
✔nCORRECTnANSWER:nA
EXPERTnRATIONALE:nPLCsnarenextensivelynusedninnmanufacturing,npackaging,nfoodnprocessing,nm
aterialnhandlingnandnothernindustrialnapplicationsnrequiringnautomatedncontrol.
3.nWhatnisnthenmainnadvantagenofnanPLCnovernconventionalnrelayncontrolnsystems?
A.nItncannotnbenreprogrammed
B.nItnrequiresnmorenphysicalnwiring
C.nItneliminatesnthenneednfornelectricalnpower
D.nItnoffersnflexible,nprogrammablencontrol
✔nCORRECTnANSWER:nD
EXPERTnRATIONALE:nPLCnprogramsncannbenmodifiednwithoutnextensivenphysicalnrewiring,nmakingn
controlnsystemsnmorenflexiblenandneasierntonmaintain.
4.nWhatndoesnPLCnstandnfor?
A.nPowernLogicnCircuit
B.nProgrammablenLogicnController
, C.nProcessnLinenComputer
D.nProgramnLoadnControl
✔nCORRECTnANSWER:nB
EXPERTnRATIONALE:nPLCnstandsnfornProgrammablenLogicnController,nannindustrialncomputerndesig
nedntoncontrolnmachinesnandnprocesses.
5.nWhichnfeaturenmakesnanPLCnsuitablenfornindustrialnenvironments?
A.nItsnsensitivityntonvibration
B.nItsndependencenonnroom-temperaturenconditions
C.nItsnruggednconstruction
D.nItsninabilityntonwithstandnelectricalnnoise
✔nCORRECTnANSWER:nC
EXPERTnRATIONALE:nIndustrialnPLCsnarendesignedntonoperateninnenvironmentsninvolvingnelectrical
nnoise,nvibrationnandnvaryingntemperaturesnwithinntheirnspecifiednoperatingnlimits.
CHAPTERn2n—nPLCnHARDWAREnANDnARCHITECTURE
6.nWhatnisnthenfunctionnofnthenPLCnpowernsupply?
A.nTonconvertnincomingnelectricalnpowernintonthenvoltagesnrequirednbynthenPLC
B.nTonwritenladdernlogicnautomatically
C.nTonmeasurenmachinenspeed
D.nTonstorenthenentirenproductionnhistory
✔nCORRECTnANSWER:nA
EXPERTnRATIONALE:nThenpowernsupplynconvertsnincomingnpowernintonregulatednDCnvoltagesnreq
uirednbynthenPLCnprocessornandnassociatednelectronics.
7.nWhichnPLCncomponentnexecutesnthencontrolnprogram?
A.nInputnmodule
B.nOutputnmodule
C.nPowerntransformer
D.nCentralnProcessingnUnitn(CPU)
✔nCORRECTnANSWER:nD
EXPERTnRATIONALE:nThenCPUnprocessesninputninformation,nexecutesnthenusernprogramnandndeter
minesnthenappropriatenoutputnstates.
AN OVERVIEW
1.nWhatnisnthenprimarynfunctionnofnanProgrammablenLogicnControllern(PLC)?
A.nTonreplacenallnelectricalnwiringninnanfactory
B.nTonperformnonlynmathematicalncalculations
C.nTonmonitorninputsnandncontrolnoutputsnaccordingntonanstorednprogram
D.nTonsupplynelectricalnpowerntonmachines
✔nCORRECTnANSWER:nC
EXPERTnRATIONALE:nAnPLCnmonitorsninputndevices,nexecutesnanstoredncontrolnprogramnandnupdat
esnoutputndevicesnaccordingntonthenprogrammednlogic.nItnisnwidelynusedninnindustrialnautomation.
2.nWhichnindustryncommonlynusesnPLCs?
A.nIndustrialnmanufacturing
B.nFashionndesignnonly
C.nGraphicnillustration
D.nMusicnproduction
✔nCORRECTnANSWER:nA
EXPERTnRATIONALE:nPLCsnarenextensivelynusedninnmanufacturing,npackaging,nfoodnprocessing,nm
aterialnhandlingnandnothernindustrialnapplicationsnrequiringnautomatedncontrol.
3.nWhatnisnthenmainnadvantagenofnanPLCnovernconventionalnrelayncontrolnsystems?
A.nItncannotnbenreprogrammed
B.nItnrequiresnmorenphysicalnwiring
C.nItneliminatesnthenneednfornelectricalnpower
D.nItnoffersnflexible,nprogrammablencontrol
✔nCORRECTnANSWER:nD
EXPERTnRATIONALE:nPLCnprogramsncannbenmodifiednwithoutnextensivenphysicalnrewiring,nmakingn
controlnsystemsnmorenflexiblenandneasierntonmaintain.
4.nWhatndoesnPLCnstandnfor?
A.nPowernLogicnCircuit
B.nProgrammablenLogicnController
, C.nProcessnLinenComputer
D.nProgramnLoadnControl
✔nCORRECTnANSWER:nB
EXPERTnRATIONALE:nPLCnstandsnfornProgrammablenLogicnController,nannindustrialncomputerndesig
nedntoncontrolnmachinesnandnprocesses.
5.nWhichnfeaturenmakesnanPLCnsuitablenfornindustrialnenvironments?
A.nItsnsensitivityntonvibration
B.nItsndependencenonnroom-temperaturenconditions
C.nItsnruggednconstruction
D.nItsninabilityntonwithstandnelectricalnnoise
✔nCORRECTnANSWER:nC
EXPERTnRATIONALE:nIndustrialnPLCsnarendesignedntonoperateninnenvironmentsninvolvingnelectrical
nnoise,nvibrationnandnvaryingntemperaturesnwithinntheirnspecifiednoperatingnlimits.
CHAPTERn2n—nPLCnHARDWAREnANDnARCHITECTURE
6.nWhatnisnthenfunctionnofnthenPLCnpowernsupply?
A.nTonconvertnincomingnelectricalnpowernintonthenvoltagesnrequirednbynthenPLC
B.nTonwritenladdernlogicnautomatically
C.nTonmeasurenmachinenspeed
D.nTonstorenthenentirenproductionnhistory
✔nCORRECTnANSWER:nA
EXPERTnRATIONALE:nThenpowernsupplynconvertsnincomingnpowernintonregulatednDCnvoltagesnreq
uirednbynthenPLCnprocessornandnassociatednelectronics.
7.nWhichnPLCncomponentnexecutesnthencontrolnprogram?
A.nInputnmodule
B.nOutputnmodule
C.nPowerntransformer
D.nCentralnProcessingnUnitn(CPU)
✔nCORRECTnANSWER:nD
EXPERTnRATIONALE:nThenCPUnprocessesninputninformation,nexecutesnthenusernprogramnandndeter
minesnthenappropriatenoutputnstates.
