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PLC FINAL Exam Questions and Answers
100% Pass
The Accumulated (ACC) value of an Up/Down counter is equal to the number of up counts
_______ the number of down counts. - ANS MINUS
Tag property local refers to module defined because tags are first defined in the - ANS I/O
module
serial comm is best described by - ANS connecting RS-232 cable (null Modem) between
devices
baud rate is how quickly data is - ANS exchanged
input images are the type of memory file used to addressed hardwired - ANS inputs
basic rule for a plc program is that the program that is currently used is the only one in -
ANS plc memory
is memory that can be overwritten often, - ANS RAM
____ stores the entire program to memory and isn't overwitten often. - ANS ROM
main use of an I/O diagram is to document the physical connections of the PLC to the machine
electrical - ANS hardware.
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circuits in I/O modules reduce the effect of line noise on the input state, electrically separate
the control circuit and field circuit voltages and prevent transient line voltage from damaging
system - ANS optical isolators
if the system has complete failure, check - ANS power supply first
_____modules, directly control AC devices - ANS TRIAC OUTPUT
____ discrete output modules use a transistor as a switching device - ANS DC
Triac is for - ANS AC
transistor is for - ANS DC
Logics are - - ANS AND, OR, NOT, NOR, NAND
counters - ANS count up, count down, latch, unlatch
routines - ANS applications intructions, inputs, outputs.
subroutines - allow for several programs on a single plc routine programs, - ANS tasks. are an
example of plc programming language projects.
Bits are - ANS integers double intergers (DINT) word boolean
5 commonly used numbering systems are - ANS hexadecimal, decimal binary octal binary
coded decimal (BCD)
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weighted value - ANS LSD (least, furthest to the right) MFD(most, furthest to the left)
a plc output is wired to a motor starter, N.O auxiallary contact from the motor starter is an
input to the plc. if the output of the plc is off then the input to the plc will be what? - ANS off
numbering systems used to display timing or counter numbers are in a - ANS decimal base
NPN device is one that can switch the negative side of the circuit while a PNP device switches
the - ANS positive side.
NPN schematic symbol points down, while PNP - ANS UP and in
RTO - ANS Retentive Timer On
NON Retentive - ANS Timer ON (TON) Timer off (TOF)
Serial communication is best described by connecting - ANS RS232 cable between cables
(null modem)
input images are the type of memory file used to - ANS address hardwired inputs
______ for a PLC program is that the program that is currently used is the only one in PLC
memory. - ANS basic rule
Ram is memory that can be - ANS overwritten often, status of input & output devices are an
exampl
_____ stores the entire program to memory and isn't overwritten often ** - ANS ROM
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Handshake is - ANS sending info (ask and receive)
battery backup for - ANS memory
most popular communication protocols are ethernet and - ANS universal serial bus (USB)
Main us of an I/O diagram is to document the physical connections of the PLC to the machine -
ANS electrical hardware.
Active low input module: Current sinking input module must be used with a - ANS current
sourcing sensor
5 features of output modules; ss dc output modules use transistors for - ANS switches
You want to look at voltage required of the load device, current draw of the load device and -
ANS number of inputs required.
the purpose of a digital output module is to energize loads in response to plc -
ANS instruction
a diode cannot be used with an AC control - ANS voltage
the best place to start when trouble shooting an issue with a PLC system is to identify the
symptoms of a - ANS specific problem
7 types of PLC faults : the first you should verify when there is a processor fault is to check the
processor fault messages on - ANS Error codes
©FYNDLAY 4
PLC FINAL Exam Questions and Answers
100% Pass
The Accumulated (ACC) value of an Up/Down counter is equal to the number of up counts
_______ the number of down counts. - ANS MINUS
Tag property local refers to module defined because tags are first defined in the - ANS I/O
module
serial comm is best described by - ANS connecting RS-232 cable (null Modem) between
devices
baud rate is how quickly data is - ANS exchanged
input images are the type of memory file used to addressed hardwired - ANS inputs
basic rule for a plc program is that the program that is currently used is the only one in -
ANS plc memory
is memory that can be overwritten often, - ANS RAM
____ stores the entire program to memory and isn't overwitten often. - ANS ROM
main use of an I/O diagram is to document the physical connections of the PLC to the machine
electrical - ANS hardware.
©FYNDLAY 1
, ©FYNDLAY 2025 ALL RIGHTS RESERVED
circuits in I/O modules reduce the effect of line noise on the input state, electrically separate
the control circuit and field circuit voltages and prevent transient line voltage from damaging
system - ANS optical isolators
if the system has complete failure, check - ANS power supply first
_____modules, directly control AC devices - ANS TRIAC OUTPUT
____ discrete output modules use a transistor as a switching device - ANS DC
Triac is for - ANS AC
transistor is for - ANS DC
Logics are - - ANS AND, OR, NOT, NOR, NAND
counters - ANS count up, count down, latch, unlatch
routines - ANS applications intructions, inputs, outputs.
subroutines - allow for several programs on a single plc routine programs, - ANS tasks. are an
example of plc programming language projects.
Bits are - ANS integers double intergers (DINT) word boolean
5 commonly used numbering systems are - ANS hexadecimal, decimal binary octal binary
coded decimal (BCD)
©FYNDLAY 2
, ©FYNDLAY 2025 ALL RIGHTS RESERVED
weighted value - ANS LSD (least, furthest to the right) MFD(most, furthest to the left)
a plc output is wired to a motor starter, N.O auxiallary contact from the motor starter is an
input to the plc. if the output of the plc is off then the input to the plc will be what? - ANS off
numbering systems used to display timing or counter numbers are in a - ANS decimal base
NPN device is one that can switch the negative side of the circuit while a PNP device switches
the - ANS positive side.
NPN schematic symbol points down, while PNP - ANS UP and in
RTO - ANS Retentive Timer On
NON Retentive - ANS Timer ON (TON) Timer off (TOF)
Serial communication is best described by connecting - ANS RS232 cable between cables
(null modem)
input images are the type of memory file used to - ANS address hardwired inputs
______ for a PLC program is that the program that is currently used is the only one in PLC
memory. - ANS basic rule
Ram is memory that can be - ANS overwritten often, status of input & output devices are an
exampl
_____ stores the entire program to memory and isn't overwritten often ** - ANS ROM
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, ©FYNDLAY 2025 ALL RIGHTS RESERVED
Handshake is - ANS sending info (ask and receive)
battery backup for - ANS memory
most popular communication protocols are ethernet and - ANS universal serial bus (USB)
Main us of an I/O diagram is to document the physical connections of the PLC to the machine -
ANS electrical hardware.
Active low input module: Current sinking input module must be used with a - ANS current
sourcing sensor
5 features of output modules; ss dc output modules use transistors for - ANS switches
You want to look at voltage required of the load device, current draw of the load device and -
ANS number of inputs required.
the purpose of a digital output module is to energize loads in response to plc -
ANS instruction
a diode cannot be used with an AC control - ANS voltage
the best place to start when trouble shooting an issue with a PLC system is to identify the
symptoms of a - ANS specific problem
7 types of PLC faults : the first you should verify when there is a processor fault is to check the
processor fault messages on - ANS Error codes
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