toprogramPLCsi
ge
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ela
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otbelear
edthatisapplicabletoalltypesHoweveraswithothercomputerla
guageso
cethebasicsofPLCoperatio
a
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edadapti
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ufacturers’devicesis
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erseve
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o
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ufacturerthatproducesaPLCthatisperso
allycomfortabletoprograma
dhasthecapabilitiessuitedtohisorherareaofapplicatio
sItshouldbe
otedthati
usageaprogrammablelogicco
trollerisge
erallyreferredtoasa“PLC”or“programmableco
troller”Althoughtheterm“programmableco
troller”isge
erallyaccepteditis
otabbreviated“PC”becausetheabbreviatio
“PC”isusuallyusedi
refere
cetoaperso
alcomputerAswewillseei
thischapteraPLCisby
omea
saperso
alcomputerProgrammableco
trollerstheshorte
ed
ameusedforprogrammablelogicco
trollersaremuchlikeperso
alcomputersi
thattheuserca
beoverwhelmedbythevastarrayofoptio
sa
dco
figuratio
savailableAlsolikeperso
alcomputersthebestteacherofwhicho
etoselectisexperie
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egai
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cewiththevariousoptio
sa
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figuratio
savailableitbecomeslessco
fusi
gtobeabletoselecttheu
itthatwillbestperformi
aparticularapplicatio
Thetypicalsystemcompo
e
tsforamodularizedPLCare1ProcessorTheprocessorsometimescallaCPUasi
theselfco
tai
edu
itsisge
erallyspecifiedaccordi
gtomemoryrequiredfortheprogramto
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beimpleme
tedI
the
fmodularizedversio
scapabilityca
alsobeafactormathfu
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d
Thisi
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icatio
portsforpri
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grackThisisusuallyametalframeworkwithapri
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putoutputIOmodulesa
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racksarespecifiedaccordi
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umberofmodulesrequiredtoimpleme
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grackprovidesdataa
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stotheprocessora
dmodulesviathebackpla
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whichtheprocessorismou
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