PLC FINAL EXAM
Decimal is a base _______ numbering system and is said to have developed from the fact that most people have ten fingers.
10
An on-delay non-retentive timer will time when the input is pressed, in 10 minutes the input is true for 10 Milliseconds every minute. What is the accumulated time after 10 minutes?
10 milliseconds
An on-delay non-retentive timer will time when the input is true, in 10 minutes the input is true for 10 Milliseconds every minute. What is the accumulated time after 10 minutes?
10 milliseconds
What is decimal number 41 converted to binary?
101001
What is decimal number 15 converted to binary?
1111
Which of the following is the number of true inputs a three input AND must have to have a true output?
3
Each decimal digit of an LED display is controlled by _______ data lines that are wired to four output terminals of a PLC output module.
4
Creating a ControlLogix project requires performing a __________ process.
7-step
A current sourcing sensor must be used with _____________?
Current sinking input module
A current sinking input module must be used with _____________?
Current sourcing sensor
The __________ function causes the machine to stop after the machine finishes the last step in its cycle.
Cycle stop
transistor is for
DC
When interfacing a PLC with a CNC, how would you interface the two machines if the PLC is a 24VDC PNP input module and the CNC is 24VDC PNP?
DIRECT WIRING FROM PLC TO CNC
Module-defined _______________ organize and store information about the module.
Data-types
The FRD instruction is an internal output instruction that converts BCD data, such as an input tag, into a(n) _________ equivalent.
Decimal
In a single-cycle program, the start and stop inputs ________ control the output.
Directly
The ________ bit is set when the instruction tag's accumulated value is equal to the preset value.
Done
The clamping cylinder is controlled with a(n) __________ solenoid valve.
Double
The Minor Fault Flag is set when a program __________ causes a Minor Fault to occur.
EXECUTION
To enable forces, click the Forces drop-list on the online toolbar and select the I/O Forcing option, then the _________________ option.
Enable all I/O forces
Sealing in a motor using seal-in logic provides no guarantee that the motor has been _________.
Energized
The Minor Fault Flag is set when a program ________ causes a minor fault to occur.
Error
7 types of PLC faults : the first you should verify when there is a processor fault is to check the processor fault messages on
Error codes
A PLC time-driven sequencing program operates by using a series of timer relays that each control a(n) ________ in the sequence.
Event
Each action is called a sequence step or _________.
Event
When the processor is in program mode, outputs can be turned on by the PLC.
FALSE
Once latched, the tag of a latch output remains a 1 even when the rung turns __________.
False
The First Scan Flag is set for only the _______ scan.
First
The LBL instruction must always be the ________ instruction in the rung.
First
A(n) ____________ is a graphical method of troubleshooting that uses block symbols connected by flow lines to show the sequence of steps to follow.
Flowchart
A programmable controller's outputs can control both ______________ and electric motors.
Fluid power
The ______ function causes the machine to stop after finishing its current step. It resumes operation beginning with the next step when a start signal is received.
Halt
The ________ shows how the machine's devices are wired to the PLC's inputs and outputs.
I/O diagram
When troubleshooting a PLC control system, the first step should be? ***
Identifying the faulty operation
A ControlLogix ____________ is the software file that stores all programming instructions, hardware configuration, and tag data for a ControlLogix processor.
Project
_____ is a type of memory commonly used for temporary storage of data that may need to be quickly changed.
RAM
is memory that can be overwritten often,
RAM
A(n) _________ type output module uses physical relay contacts inside the module that open and close to make or break the circuit.
RELAY
The word discrete means _____________.
Separate
The JSR instruction is a program control instruction that causes the processor to run a(n) ___________.
Subroutine
The ________ instruction converts a decimal data tag, such as the Preset value of a Counter instruction, into a BCD value.
TOD
____________ are text-based names given to PLC memory locations.
Tags
The TOD instruction's destination identifies the _________ address of the converted source value.
Target
if the force indicator is not illuminated, other devices connected to the same module and functioning correctly and you have tested contactor individually and found functionally
The PLC is not in run mode
PLC solid state outputs can be directly interfaced to another machine's inputs only if the ____________ and transistor types are compatible.
VOLTAGES
In event of a power interruption, a _____ is used in some processors to provide power to the RAM.
capacitor
wiring a field device causes the majority of PLC system
failures
input images are the type of memory file used to addressed hardwired
inputs
the purpose of a digital output module is to energize loads in response to plc
instruction
Bits are
integers double intergers (DINT) word boolean
What is the function of an input module?
interface between on and off devices
MCR instructions can be used as a(n) __________ to allow only a portion of a PLC program to operate at one time.
interlock
the best place to start when trouble shooting an issue with a PLC system is to identify the symptoms of a
specific problem
After _______ and _______, timers and counters are the most commonly used PLC instructions.
Coils, contacts
Handshake is
sending info (ask and receive)
subroutines - allow for several programs on a single plc routine programs,
tasks. are an example of plc programming language projects.
When two different machines are interfaced
the input of one machine is activated by the output of another
you should document the program after altering it to do an additional task by date,
the intended effect, & which line of the program you changed
an advantage of adding comments to ladder rungs and individual program instructions is because .
they improve execution efficiency
A few applications that use _______ functions include energy management, mixing operations, dwell functions, communication, queueing, and alarms.
timed
most popular communication protocols are ethernet and
universal serial bus (USB)
To verify that an output is sending the correct signal to a relay from the PLC output module you should
use a voltmeter to verify the correct voltage to the relay
a diode cannot be used with an AC control
voltage
The "ON state input voltage range" specification refers to:
voltage at which the input signal is recognized as being ON.
retentive timer reset is necessary to
clear out accumulated value
The ______________ dialog is a Studio 5000 software utility that displays configuration, operation, and status information offline and online.
Controller properties
Most PLCs have two basic counter instructions: Count up (CTU) and ________________.
Count down (CTD)
_______ instructions are used to activate or deactivate devices after a predefined number of cycles.
Counter
Some applications that use _________ are motors, production, alarms, and welding.
Counters
serial comm is best described by
connecting RS-232 cable (null Modem) between devices
timers time intervals and counters
count events
counters
count up, count down, latch, unlatch
Active low input module: Current sinking input module must be used with a
current sourcing sensor
The six basic components of most PLCs are the power supply, the input modules, the output modules, the programming device, Processor module, and the ______________?
I/O CHASIS
___________ a PLC program puts all outputs in startup state and checks inputs to verity that the process can safely be restarted.
Initializing
PLC memory files use _____________ to address hardwired inputs?
Input images
The first step in testing a PLC input device is to operate the input device and observe the PLC's ____________ indicator.
Input status
One application of a(n) ______________ instruction is to control the simultaneous start and stop of several outputs.
Internal output
In the module tag Local:1:I: Data, Local refers to the modules _______________.
Location
The Accumulated (ACC) value of an Up/Down counter is equal to the number of up counts _______ the number of down counts.
MINUS
Time-driven sequencing can be used to control operations that are based on time, such as heating, cooling, or _________ of materials.
MIXING
The ControlLogix family of programmable controllers has a test mode that enables the user to test program operation without energizing ____________.
Outputs
The BCD system provides a convenient means to handle large numbers that need to be input to or output from a(n) _________.
PLC
The PLC power supply module normally is rated to provide the power for:
PLC backplane and I/O modules.
When voltage is applied to input terminal Local:1:I:DATA.0 of a PLC, a programmed XIC instruction with the same address will ________________.
True
PLC input modules vary according to four features: ________________, level of voltage, number of inputs and active high or active low input.
Type of current
NPN schematic symbol points down, while PNP
UP and in
numbering systems used to display timing or counter numbers are in a
decimal base
online editing relies on an active serial communication between devices, which best
describes the difference between online & offline program editing
indicator lights on a plc are used for
diagnostics & maintenance
Count down (CTD) instructions are usually combined with Count up (CTU) instructions to form a(n) ___________ counter.
down
Main us of an I/O diagram is to document the physical connections of the PLC to the machine
electrical hardware.
The ___________ bit is set when the timer instruction is enabled and reset when the instruction goes false.
.DN
If a 4 digit LED display reads 2 7 9 2 in decimal what is the equivalent in binary?
0010011110010010
The .ACC increases by what amount when the input to a CTU counter goes true?
1
PLC input lights are off, but if they are on it could be a
faulty wiring , a defective sensor, or a faulty power supply
battery backup for
memory
to test a discrete input module. establishing a force is
not a good way
Programmable logic controllers are categorized according to the
number of I/O points.
You want to look at voltage required of the load device, current draw of the load device and
number of inputs required.
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?
off
a wireless connection is not critical for
online editing
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
optical isolators
the remote function of a plc allows the user to
perform the plc operations status to be changed on line.
basic rule for a plc program is that the program that is currently used is the only one in
plc memory
NPN device is one that can switch the negative side of the circuit while a PNP device switches the
positive side.
if the system has complete failure, check
power supply first
When troubleshooting, observing that all PLC indicators are off could be caused by a(n) _______________ or a bad chassis power supply.
Complete power failure
Serial communication is best described by
Connecting RS-232 cable between two devices
The controller module's _________ indicator flashes amber when forced I/O conditions appear in the user program and appears solid amber when those conditions are enabled.
Force
The advantage of a JMP instruction is that is reduces processor ________ time.
Scan
Multiple safety interlock can be used in a program by placing input instructions in ________ with each other on a rung.
Series
PLC input module has the following purpose.
It connects signals from the process as inputs to the PLC
at the start of an individual start up when trouble shooting a suspected PLC power supply problem and the input AC voltage to a PLC is good
the power supply fuse and the input voltage selection jumper should be checked.
The First Scan Flag tag name is _________.
S: FS
In most pick and place robotic programs each step of the program application depend's on what kind of input type?
SENSOR INPUT SIGNAL
A common special function is to provide the ability to change the mode of operation from automatic to __________.
Manual
Programmers often use a latch as a ___________ device when input conditions are the same at different steps in a routine.
Memory
A single cycle program cycles _______ each time the operator presses the start pushbutton.
Once
5 features of output modules; ss dc output modules use transistors for
switches
Using Seal-in or latch/unlatch in ladder logic indicates that
the logic will keep the command (usually momentary)
The I/O system provides an interface between:
the CPU and field equipment.
Generally, a(n) _________ is used to control the overall operation of automatic work cells and computer integrated manufacturing systems.
PLC
The Minor Fault Flag's tag name is ___________.
S: Minor
The drill cylinder is controlled with a(n) ______ solenoid valve.
Single
The __________ instruction is used to turn outputs on or off after the timer has been disabled (or off) for a preset time interval.
TOF
When a timer rung is true, the timer begins to increment the ACC value at a rate specified by the time base. When the rung goes false, the timer resets the ACC value.
TON
Most electronic sensors use a _____________ output to send a signal to the PLC.
TRANSISTOR
VDC discrete output modules use a switching device called a _____________.
TRANSISTOR
The emergency stop function should always be __________ into the power supply of the PLC's outputs.
Hardwired
All devices that communicate with the controller must be added to the controller projects __________configuration.
I/O
When a field device contact connected to the input module closes:
a logic 1 is recorded in the memory location of the contact with the same address.
The most common form of memory used to store, back up, or transfer PLC programs is: RAM Flash EEPROM EEPROM both b and c
both b and c Flash EEPROM, EEPROM
main use of an I/O diagram is to document the physical connections of the PLC to the machine electrical
hardware.
The file extension given to a Studio 5000 project is ___________.
ACD
Most automatic machines perform a number of __________ to accomplish the task for which they have been designed.
ACTIONS
a hardwired master control relay (MCR) is used as a safety device to remove power from all
PLC outputs to disable all actions
A communication error between an I/O module and the owner controller causes the controller to fault, program operation to stop, and the output modules" OK indicators to flash ________.
Red
The specific order in which automatic machines perform actions is called a(n) ___________.
Sequence
Input and output modules communicate with the CPU how?
Series of electrical connections in the backplane
_____modules, directly control AC devices
TRIAC OUTPUT
Three common stop functions are:
Cycle stop, halt, emergency stop
The First Scan Flag is often used in applications to __________ a program to a known state on power-up of the controller.
Initialize
Documenting physical connections of the PLC to machine electrical hardware is known as ______________.
Main use of input and output diagrams
A motor used on a conveyor system turns on the output for .50 seconds, then turns off for 2 seconds. How many timers are needed to perform this task?
2
The count up (CTU) instruction increases the instruction tag's ___________ value by one each time the rung containing the counter goes from false-to-true.
ACC
An MCR is used as a safety device to remove power from all PLC outputs to disable all _________.
ACTIONS
A ____ is an example of a device that could be used to provide a discrete input to a PLC. Pushbutton Selector switch Limit switch All of the above
ALL OF THE ABOVE
In a(n) _____________ PLC input module, an input is on if voltage is applied to the input terminal and off if no voltage is applied to the input terminal.
Active high
A ____ is an example of an actuator that could be controlled by a discrete output from a PLC.
MOTOR STARTER
___________ descriptions are used to describe the tag/instruction combinations in ladder logic.
Main operand
A(n) __________ shows how machine action affects the PLC inputs and how the PLC outputs affect machine action.
Power diagram
The PLC requires that AC power be supplied from an external source to its chassis ___________.
Power supply
The _________ value is the length of time the timer instruction must be enabled for the instruction's DN bit to set.
Preset
Two classifications of PLC timers are ______________________.
Retentive and Non-retentive
A specific application of an interlock program is the ___________ motor control program.
Reversing
A BCD thumbwheel switch consists of one or more ________ switches that each control four data lines.
Rotary
A subroutine is a program which can be executed by another ____________
Routine
A(n) ____________ is a collection of program instructions in a single programming language, such as ladder logic, that provides instructions to a controller.
Routine
__________ description is used to describe the routine and its operation.
Routine
The JSR instruction's _____________ field identifies the name of the subroutine.
Routine name
The ________________ is the area that displays the ladder logic for the routine.
Routine view
______________ contain the actual operating instruction (or executable code) that determines the operation of the controller.
Routines
Processor module indicators include ________, _________, ________, and ________
Run, Force, SD, OK
______ comments contain information pertaining to the rung or group of rungs.
Rung
A control system should be designed so that devices automatically go to a(n) _______ condition should control power be lost.
SAFE
The Up/Down counter's Done (DN) bit is ______ whenever the accumulated (ACC) value is greater than or equal to the Preset (PRE) value and reset when the value is less than the preset (PRE) value.
SET
The four languages used to program a ControlLogix PLC are _____________________, Structured text, FBD, and ladder logic.
SFC
The basic concept of a(n) _______________ is to prevent some event from happening unless certain conditions are present that indicate it is safe to do so.
Safety interlock
After coils and contacts, __________ and __________ are the most commonly used PLC instructions.
TIMERS, COUNTERS
When voltage is applied to input terminal Local:1:I:Data.0 of a PLC, a programmed XIC instruction with the same address will ________________.
TRUE
A __________ is a detailed sequence of operation that shows the on/off status of every input and output device/address for each step in the sequence.
TRUTH TABLE
An MCR zone uses ________ MCR coils: one on the MCR rung and one on the END MCR rung.
TWO
The controller's __________area contains and schedules all of the user logic files and may contain from 1 to 32 user defined tasks.
Task
A motor starter requires only a very small current from the PLC to energize its coil, but its __________ can handle a very large current to the motor.
Contacts
Mechanical input devices, such as pushbuttons and limit switches, can be tested out-of-circuit using a(n) ___________ test.
Continuity
In the ___________ cycle program, the start and stop pushbuttons, PB1 and PB2, control an internal coil instruction that controls the start and stop of the sequence.
Continuous
When troubleshooting, observing that all input I/O state indicators are off (but processor indicators are on) means that _____________ to the input and output devices has been lost.
Control power
When voltage is applied to input terminal Local:1:I:DATA.1 of a PLC, a programmed XIO instruction addressed Local:1:I:DATA.1 will be _________________.
FALSE
The five types of numbering systems commonly used by PLC's are decimal, binary, BCD, octal, and ________________.
Hexadecimal
Tag property local refers to module defined because tags are first defined in the
I/O module
__________ a PLC program puts all outputs in startup state and checks inputs to verify that the process can safely be restarted.
INITIALIZING
One of the advantages of a PLC is that is permits many instructions to be controlled by one _________.
INPUT
Interfacing between the on/off field devices is the function of what?
INPUT MODULE
MCR instructions can be used as a(n) ___________ to allow only a portion of a PLC program to operate at one time.
INTERLOCK
PLC input/output diagrams are used to show the specific physical connections between the ____________________ and the PLC I/O terminals.
INTERNAL DEVICES
The PLC memory, known as an _________, includes firmware, ladder routines, tags, configuration data, and data tables.
Image
the following happens to the information of a sequencer as it advances through its steps it transfers from the
outputs module to the input module
Ram is memory that can be
overwritten often, status of input & output devices are an exampl
At the start of the PLC scan the:
status of all inputs are read.
To prevent arcing of hard contacts, a(n) __________ (often called a voltage snubber), is connected across the coil leads to short circuit the inductive kick voltage around the output module.
surge suppressor
What is decimal number 57 converted to binary?
00111001
What is decimal number 6 converted to binary?
0110
baud rate is how quickly data is
exchanged
The rate at which how fast data is sent over a serial line in units of bps.
Baud
The largest-valued symbol of the system is always one less than the __________.
Base
A discrete output interface module is designed to provide:
ON/OFF switching of the output field device.
The manual mode allows the _________ to operate the actuators one at a time by pressing pushbuttons or operating selector switches.
OPERATOR
The output or _________ instruction is used to control the application of voltage to a real-world device.
OTE
When the rung is true, the __________ instruction writes a zero to its tag.
OTU
The ________ module, being an industrially hardened computer, is susceptible to hardware failures just like any other computer.
Processor
The part of a PLC that executes the logic program is the ___________.
Processor
PLC input modules sense the condition of real-world input devices and transmit this information to the PLC's _________________.
Processor module
____________________ is a method of using logic in a PLC program to cause an output to turn on or off if certain inputs or outputs are in a particular state.
Program interlocking
A programmer uses the truth table and I/O diagram to develop the ___________ for the PLC application.
Program logic
Input instructions having output addresses can be used to perform memory functions by using _______________.
Seal-in logic
RTO
Retentive Timer On
you will not find provisions for human intervention beyond e-stop in the code of
automatic program
An AC reversing motor starter controls an electric motor that draws a small current. What is an AC reversing starter?
two contactors interlocked to run one direction at a time
Which base does hexadecimal numbering use?
16
The BCD system uses _______ bits to represent each decimal digit.
4
Studio 5000 provides _____ pre-defined data types to the user that are the building blocks of all tags and tag structures used in ControlLogix projects.
5
If an XIC instruction in a PLC program has a tag name of Timer_1.DN when will the DN bit be TRUE (on) if a Off-Delay Non-Retentive timer is used? when the N.O. pushbutton is pressed before the .ACC equals the .PRE while the TT bit is starts timing All of the above
ALL OF THE ABOVE
When selecting a discrete output module which of the following is correct? Number of outputs required Current draw of the load Voltage required of the load All of the above
ALL OF THE ABOVE
In PLC program, arranging two XIC instructions in series is an example of a(n) ______ logic element.
AND
Logics are -
AND, OR, NOT, NOR, NAND
The _________________ displays the actual time that the timer instruction has been enabled.
Accumulated value
Time-driven sequencing can be used in applications where _____________ is not consistent enough to use limit switches for event-driven sequencing.
Actuator positioning
A(n) _______ is another name that references an existing tag.
Alias
When selecting a discrete output module which of the following is correct? Number of outputs required Current draw of the load Voltage required of the load All of the above
All of the above
A relay connect to an output is always on, even when input sensors that should operate it have no effect. Which of the following is the possible problems?
An output FORCE is in place indicated by an illuminated FORCE light on the processor control
A(n) _______ is a collection of numerically indexed tags.
Array
A(n) _____________ is a name, property, parameter, or value for the device for which the object data applies.
Attribute
Most _________ machines are designed with more than one type of stop function to meet various situations where a machine should be stopped.
Automatic
The normal operating model of most machines is the ___________ mode.
Automatic
The programming technique that controls a single actuator event-driven sequence can also be applied to machines with multiple actuators. A common example is the ____________ application.
Clamp and drill
A flashing red I/O module status (OK) indicator indicates that _____________ between the controller and module has timed out.
Communication
A tag structure contains _________________, fault, and terminal status for a module.
Configuration
The numbering system you use everyday to count money, keep score, add, subtract, and multiply is known as the ______________ numbering system.
Decimal
The count down (CTD) instruction ___________ the accumulated value by one each timer the rung containing the instruction goes from false to true.
Decreases
If an output device doesn't work even though the corresponding output terminals are energized, the problem is either in the ____________ or interface wiring.
Device
The PLC output ____________ should include the Normally closed contacts of the motor starter if applicable.
Diagram
If a Normally open auxiliary pushbutton is connected to a normally closed contact in the ladder logic, pressing the pushbutton will cause the contact to turn ____________.
FALSE
When first MCR is false all outputs within the fence are _________, even if rung inputs are true within the fence.
FALSE
If a Normally open auxiliary pushbutton is connected to an XIO contact, pressing the pushbutton will cause the contact to turn ____________.
False
The output interface module connects to:
Load devices such as lamps or solenoids
The MainRoutine is the ________ routine run when the controller triggers a task.
First
An MCR instruction that is used with the _________________ can also be used to initialize a PLC application to some predetermined state.
First Scan Flag
Five multiple motors need to be sequenced started at different times. What type of timer and how many would a technician use to complete this task?
Five non-retentive on-delay timers
The ControlLogix instruction set provides two instructions used to extract data from and insert data into a controller's system data objects: _______ and ________.
GSV, SSV
In an active low output module, the ___________ of the source voltage is switched by the transistor output.
Ground
PNP transistors provide sensor outputs with an active _______ signal.
HIGH
PLC output module has the following purpose.
It sends signals from the PLC as inputs to field devices.
When the ______ instruction is energized, all program logic between it and the LBL instruction is frozen in its last state.
JMP
When the __________ instruction is energized all program logic between it and the LBL instruction is "frozen" in its last state.
JMP
The JMP instruction is a program control instruction which, when energized, causes the PLC processor to ___________ rungs of ladder logic.
JUMP OVER
A JMP instruction must always be used with a(n) ________ instruction.
LBL
The ______________ window is used to develop ladder logic routines for ControlLogix projects.
Ladder editor
When a JSR instruction is de-energized, all outputs in the subroutine remain in their __________.
Last state
PLC discrete outputs turn real-world __________ devices on or off as directed by the PLC.
Load
If electrical power is lost, the valves will switch to their __________ states.
Natural
____________ refers to program logic that places one branch circuit inside of another.
Nesting
The ________________ dialog is used to name the controller and configure various aspects of its hardware.
New controller
A(n) __________________ timer instruction resets whenever the input is de-energized.
Non-retentive
When a rung goes false the timer returns to zero, what timer is being used to cause this action?
Non-retentive timer
When its rung is false the OTL instruction does ______________.
Nothing
Status indicators are provided on each output of an output module to indicate that the:
OUTPUT IS ACTIVE
A power diagram shows how the machine action affects the PLC's inputs and how the PLC's __________ affect the machine action.
OUTPUTS
__________ are data structures used to store status and identifying data about the controller and its operation, hardware, and program.
Objects
In the case of outputs, the Force On function is used to turn an output device ______, regardless of program or processor logic.
On
The first step in troubleshooting the ControlLogix chassis power supply is to verify that the power supply is __________.
On
The PLC uses the status of the tags as it examines input logic and updates output tags (also Boolean) with at 1 or 0 to turn the appropriate output device _____________.
On or off
A counter instruction tag's Done (DN) bit is set when the accumulated value is greater than or equal to the _________ value.
PRE
Program control instructions alter the __________ of a PLC from its normal sequence.
PROGRAM SCAN
An example of an OR logic element in a PLC program would be the arrangement of two XIC instructions in ___________.
Parallel
PLC seal-in logic works by using a second XIC instruction that is connected in __________ with the XIC instruction which turns on the output.
Parallel
Manufacturers' catalogs refer to the number of inputs as the number of ____________.
Points
A(n) ________ diagram shows the sensors and actuators that are wired as inputs and outputs to the PLC.
Power
ControlLogix chassis power supplies provide 1.2 VDC, 3.3 VDC, 5 VDC, and 24 VDC power directly to the chassis backplane for the ____________ and I/O modules contained in the chassis.
Processor
________________ is the user text associated with the rungs and instructions of a controller project that explains the operation of that item.
Project documentation
A technician knows that the PLC program is not receiving a start command from a switch in the field. How could the technician determine if the problem is a bad switch or a bad input module?
Put a force on the switch's input address
The following statement that does not apply to the optical isolator circuit used in I/O modules is that it: separates high voltage and low voltage circuits rectifies AC signals. prevents damage caused by line voltage transients. reduces the effect of electrical noise. ***
RECTIFIES AC SIGNALS
The ________ instruction zeros a counter tag's accumulated (ACC) value and clears all of its status bits.
RES
____ stores the entire program to memory and isn't overwitten often.
ROM
_____ stores the entire program to memory and isn't overwritten often **
ROM
_____memory is used by the PLC's operating system. **
ROM
The processor's _______ and ______ indicators should be solid green if it is operating correctly and in run mode.
RUN, OK
Count Down (CTD) instructions are ________ used alone in PLC programs.
Rarely
An example of a PLC program that performs an event-driven sequence is a(n) ___________ cylinder program.
Reciprocating
Solid state AC output modules use a special kind of solid-state device called a(n) ____________.
TRIAC
The __________ instruction is an output instruction used to reset timers having the same tag name.
Reset
The TON instruction is similar to the RTO instruction, however, the TON instruction tag _______ when the instruction is de-energized.
Resets
_____ networks are protection devices that are used to reduce the problems with AC electricity in relay-type output modules.
Resistor & Capacitor
Latch instructions are said to be _____________in that they retain their state when powered down.
Retentive
Program control instructions alter the _____________ of a PLC from its normal sequence.
STARTUP
The base of a numbering system determines the total number of ___________ used in that system.
SYMBOLS
The PLC programs are designed so that the machine stops ____________.
Safely
The reason that different valves are used for the clamp and drill cylinders is __________.
Safety
Two applications in which interlocks are used are sequencing and ________.
Safety
One way of locating component failure is with the five __________.
Senses
Latch and unlatch instructions are often paired by using the same _______ for both instructions.
Tag
One method of controlling multiple outputs at the same time is by placing each output on a separate rung and using multiple input instructions with the same ____________.
Tag
_________ are text-based names for areas of memory in the ControlLogix processor used to store information about the machine or process being controlled.
Tags
A technician has recently added a new sensor, the sensor does not seem to be working correctly. Which of the following would the technician check first?
The wiring of the switch
What happens when a RTO timers .ACC value equals its .PRE value?
Timer DN Bit Activates
NON Retentive
Timer ON (TON) Timer off (TOF)
The purpose of a digital Output module is _______________________?
To energize loads in response to PLC ladder logic contacts
The purpose of a digital output module is _____________.
To energize loads in response to PLC ladder logic contacts
Which of the following is not a function of a PLC programming device?
To execute the user program
________________ is the process of finding the cause or fault of a machine malfunction.
Troubleshooting
If a Normally open auxiliary pushbutton is connected to a XIC contact, pressing the pushbutton will cause the contact to turn ____________.
True
Expressing numbers greater than the largest-valued symbol is done by assigning a weighted __________ to each position from right to left.
Value
The most common of PLC system failures are:
Wiring and input devices
A normally closed auxiliary pushbutton is used with a __________ instruction to turn off a seal-in logic output.
XIC
Auxiliary Stop pushbuttons are always ______ contacts in ladder logic.
XIC
One function of a PLC input interface module is to:
accept signals from field devices and convert them into signals that can be used by the processor.
The Done bit sets when the instruction tag's _____________ value is equal to the preset value.
accumulated
input images are the type of memory file used to
address hardwired inputs
when a hardwired master control relay (MCR) is automatically de-energized some input status lights are on, the cpu running light is on, and
all action output status light are off
routines
applications intructions, inputs, outputs.
______ for a PLC program is that the program that is currently used is the only one in PLC memory.
basic rule
A BCD _____________ is an input device that enables a machine operator to adjust a PLC instruction's preset value without having to use a programming terminal.
Thumbwheel switch
Triac is for
AC
ControlLogix timers have only one time base, ____________ second(s).
0.001
Boolean tags are _________ memory location used to store the status, such as the on/off condition, of a device or instruction.
1 BIT
The rate at which data is sent over a serial line in units of bps
BAUD
To distinguish the BCD numbering system from binary, a(n) _______ designation is placed to the right of the least significant digit.
BCD
The ____________ of I/O chassis contains a circuit board that provides the path through which modules communicate and the DC power is supplied to all modules.
Backplane
In the module tag Local:1:I: DATA, Local refers to the modules _______________.
Location
____ discrete output modules use a transistor as a switching device
DC
Which is proper sequence of operation within a PLC?
Examine inputs, perform logic, update outputs
When two machines are not compatible, the machines are interfaced using ____________ connections.
Indirect
The outputs of a programmable controller can be used to control an output device directly or ______________.
Indirectly
One of the advantages of a PLC is that it permits many instructions to be controlled by one _________.
Input
A rung that uses a(n) _____________ can be used to control the start/stop of any automatic program.
Internal coil
A(n) _________ display is an output device that enables a machine operator to view the Accumulated or Preset value of an instruction without the use of a programming terminal.
LED
The BCD numbering system is used with BCD thumbwheel switches and ____________.
LED displays
PLC routines can use timers as well as ____________ to sequence events.
LIMIT SWITCHES
weighted value
LSD (least, furthest to the right) MFD(most, furthest to the left)
PLC troubleshooters should use a(n) _____________ approach to isolate the cause of the problem.
Methodical
Location, slot, and data type refer to which of the following?
Module defined
Input instructions having ___________ addresses function as dictated by the state of the OTE output instruction.
Output
Serial communication is best described by connecting
RS232 cable between cables (null modem)
The ___________ method of troubleshooting is usually the worst method to use and will be the slowest if the circuit/system is large.
Shotgun
Which of the following status indicator light conditions is likely to result when a hardwired master control relay (MCR) is automatically de-energized?
Some input status lights are on, the CPU RUNNING light is on, and all action output status lights are off
The TOD instruction's _________ field identifies the constant decimal value or tag address that is to be converted to an equivalent BCD value.
Source
Seal-in programs are commonly used to control the _____________ of electric motors and is a building block of most other machine control programs.
Start/stop
Troubleshooting a ControlLogix processor requires using the processor's _________ indicators to determine the operating condition of the processor.
Status
After identifying the problem (or symptom), the next step is to check the ____________.
Status indicators
The GSV instruction's Dest field identifies the user-created tag where the data will be ________.
Stored
The MainRoutine may contain all of the program's logic or it may contain instructions that call other routines called ______________.
Subroutines
In the ________________ method of troubleshooting, the troubleshooter isolates the problem in a system according to whether or not the component could cause the symptoms observed.
Symptom & Cause
Because downtime is so expensive, most troubleshooters in manufacturing environments perform _________ level troubleshooting only.
System
A(n) ____________ is a detailed sequence that shows the on/off status of every input and output device/address for each step in the sequence.
Truth table
There are ________ ways to have more than one output controlled with the same input logic.
Two
a major difference between manual mode and an automatic mode of a plc controlled machine is the logic uses
different inputs for the operator
5 commonly used numbering systems are
hexadecimal, decimal binary octal binary coded decimal (BCD)
In industry, automatic machines must perform operations __________.
repeatedly
In industry, automatic machines must perform operations ____________.
repeatedly
if a known good input causes the light to illuminate on the input modules but the PLC program fails to respond to the input
the key switch is in REM
Like the CTU instruction, the CTD instruction uses ________ DINT members in its tag structure.
three
_______ instructions are used to activate or deactivate a device after a predefined time.
timer
