Title: Final Test
Course: Programmable Logic Controls (IC 107-IC 107) > Section: Assessments

Q: A consecutive group of data memory words may be referred to as either words or registers.
- True
- False
A: True

Q: A lamp is to be switched off 10 seconds after a switch has been switched from it's on to off position. The most directly applicable timer to use would be the off-delay nonretentive timer.
- True
- False
A: True

Q: A one-shot, or transitional, contact:
- operates the same as an NO contact instruction.
- operates the same as an NC contact instruction.
- operates the same as a timed closed contact.
- closes for only one program scan when actuated.
A: operates the same as an NO contact instruction.

Q: A programmed XIO instruction:
- with a bit status of 1 will not have logic continuity.
- is examined for an OFF condition.
- is examined for an ON condition.
- both a and b.
A: with a bit status of 1 will not have logic continuity.

Q: A small current flows through a solid-state proximity sensor even when the output is turned OFF.
- True
- False
A: True

Q: A(n) __________ scan pattern examines instructions rung by rung.
- horizontal
- vertical
- input
- output
A: horizontal

Q: An actuator is a device that:
- changes AC to DC.
- changes DC to AC.
- converts an electrical signal into mechanical movement.
- converts mechanical movement into an electrical signal.
A: changes AC to DC.

Q: An analog input or output is a signal that varies continuously within a certain range.
- True
- False
A: True

Q: As the sequencer advances through the steps, data is transferred:
- through the sequencer file from B3:0 to B3:4.
- through the sequencer file from B3:4 to B3:0.
- from the output word to the sequencer.
- from the sequencer to the output word.
A: through the sequencer file from B3:0 to B3:4.

Q: Assume output SOL C is energized at the time the MCR instruction makes a true-to-false transition. As a result, output SOL C will:
- de-energize.
- remain energized
- remain energized but still be controlled by inputs LS3 and LS4.
- de-energized but still be controlled by inputs LS3 and LS4.
A: de-energize.

Q: Assume that the input pushbutton is pulsed 60 times after the counter had first been reset. After this operational sequence:
- the light would be on and the accumulated count would be 10.
- the light would be off and the accumulated count would be 10.
- The light would be on and the accumulated count would be 60.
- the light would be off and the accumulated count would be 60.
A: the light would be on and the accumulated count would be 10.

Q: Assume that the NC stop button is replaced with an NO stop button and that the program is changed so it operates as before. Should the field wire connected to one end of the stop button break off:
- the motor would stop automatically.
- pressing the stop button would stop the motor.
- pressing both the start and stop buttons would stop the motor.
A: the motor would stop automatically.

Q: Bits of an output word not used by the sequencer can be used elsewhere in your program.
- True
- False
A: True

Q: Destination is where the result of the instruction is stored.
- True
- False
A: True

Q: For the on-delay timer instruction shown the timer number is:
- 0
- 200
- T4:3
- 0.1
A: 0

Q: For the program shown, instruction B represents an:
- Examine IF Closed instruction.
- Examine If Open instruction.
- Output Energize instruction.
- Input Energize instruction.
A: Examine IF Closed instruction.

Q: For the programmed timer circuit shown the _________ bit of the timer functions similar to an instantaneous contact.
- DN
- EN
- PB1
- PB2
A: DN

Q: For the programmed timer circuit shown, assume the switch is closed for 5 seconds and than opened. After 12 seconds have elapsed motor(s) ________ will still be operating.
- M1, M2, M3
- M2, M3
- M3
A: M1, M2, M3

Q: For the timer program shown, output C is switched ON when:
- power is applied.
- input A is closed.
- the timer is accumulating time.
- the accumulated value equals the preset value.
A: power is applied.

Q: For there to be a continuous logic path from left to right across the rung:
- I/1, I/2, and I/3 must all be at logic 1.
- I/1, I/2, and I/3 must all be at logic 0.
- I/1 and I/2 or I/3 must be at logic 1.
- I/1 and I/2 or I/3 will be at logic 0.
A: I/1, I/2, and I/3 must all be at logic 1.

Q: In an up-counter, when the accumulated count exceeds the preset count without a reset, the accumulated count will:
- set itself to zero.
- start decrementing.
- continue incrementing.
- hold the accumulated value.
A: set itself to zero.

Q: In the hardwired relay control circuit shown, when the switch is closed, CR coil is:
- energized, and the red and green lights are both on.
- de-energized, the red light is off, and the green light is on.
- energized, the red light is on, and the green light is off.
- energized, the red light is off, and green light is on.
A: energized, and the red and green lights are both on.

Q: In the timer program shown, solenoid B is energized:
- as soon as the start button is pressed.
- 5 seconds after the start button is pressed.
- 10 seconds after the start button is pressed.
- 15 seconds after the start button is pressed.
A: as soon as the start button is pressed.

Q: It takes the processor exactly the same amount of time to examine different types of instructions.
- True
- False
A: False

Q: Misunderstanding the way the PLC scans a program can cause programming bugs.
- True
- False
A: True

Q: Output PL2 will be energized:
- until the accumulated value equals the preset value.
- when the accumulated value equals the preset value.
- only when the accumulated value exceeds 10.
- only when the accumulated value is zero.
A: until the accumulated value equals the preset value.

Q: PL1 will be on whenever the current temperature is:
- greater than the preset temperature.
- less than the preset temperature.
- greater than the upper temperature limit.
- less than the lower temperature limit.
A: greater than the preset temperature.

Q: Programmed counters can:
- count up.
- count down.
- be combined to count up and down.
A: count up.

Q: The "ON state input voltage range" specification refers to:
- the type of voltage device that will be accepted by the input.
- range of leakage voltage present at the input in its ON state.
- minimum and maximum output operating voltages.
- voltage at which the input signal is recognized as being ON.
A: the type of voltage device that will be accepted by the input.

Q: The address for the point on the I/O module would be:
- I:2/8
- I:8/2
- O:8/2
- O:2/8
A: I:2/8

Q: The Allen-Bradley SLC-500 address O:3/0 refers to an:
- Input module in slot 3, terminal 0.
- Output module in slot 3, terminal 0.
- Input module in slot 0, terminal 3.
- Output module in slot 0, terminal 3.
A: Input module in slot 3, terminal 0.

Q: The counter RES instruction:
- is used to reset the counter.
- is given the same reference address as the counter instruction.
- decrements the count when actuated.
- both a and b.
A: is used to reset the counter.

Q: The device represented by the symbol is a:
- drum switch.
- selector switch.
- sequence switch.
- toggle switch.
A: drum switch.

Q: The Examine If Open instruction:
- is also known as the Examine-Off instruction.
- is also known as the XIO instruction.
- looks and operates like a normally closed relay contact.
A: is also known as the Examine-Off instruction.

Q: 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 citcuits.
- rectifies AC signals.
- prevents damage caused by line voltage transients.
- reduces the effect of electrical noise.
A: separates high voltage and low voltage citcuits.

Q: The immediate input and output instructions provide a way of:
- ending the program immediately.
- restarting the program immediately.
- temporarily interrupting the program scan to allow selected bits in the data table to be updated.
- temporarily interrupting the program scan to reset all bets in the data table to zero.
A: ending the program immediately.

Q: The jump (JMP) instruction is used to jump over certain program instructions if certain conditions exist.
- True
- False
A: True

Q: The latch and unlatch instructions would be classified as:
- retentive outputs.
- nonretentive outputs.
- condition instructions.
- unconditional instructions.
A: retentive outputs.

Q: The logic rung is telling the processor to copy the data stored in word:
- N7:30 to word N7:20 when input A is true.
- N7:20 to word N7:30 when input A is true.
- N7:30 to word N7:20 when input A is false.
- N7:20 to word N7:30 when input A is false.
A: N7:30 to word N7:20 when input A is true.

Q: The logic rung shown is an example of a:
- data compare instruction.
- data move instruction.
- timer instruction.
- counter instruction.
A: data compare instruction.

Q: The logic rung shown:
- has logic continuity.
- does not have logic continuity.
- will cause output PL1 to be energized.
- both a and c.
A: has logic continuity.

Q: The MCR instruction can only be programmed to control an entire circuit.
- True
- False
A: False

Q: The off-delay timer (TOF) starts timing when the timer's:
- ladder rung switches from false to true.
- ladder rung switches from true to false.
- accumulated value equals its preset value.
- accumulated is greater than its preset value.
A: ladder rung switches from false to true.

Q: The output of the counter is energized whenever the accumulated count is less than or equal to the preset count.
- True
- False
A: False

Q: The PLC power supply module normally is rated to provide the power for:
- all field devices.
- input field devices only.
- output field devices only.
- PLC backplane and I/O modules.
A: all field devices.

Q: The power required to operate the logic circuits of the processor unit is typically:
- low voltage ac.
- high voltage ac.
- low voltage dc.
- high voltage dc.
A: low voltage ac.

Q: The processor may perform functions such as timing, counting, and comparing in addition to logic processing.
- True
- False
A: True

Q: The source of a move instruction contains the address where the instruction sends a copy of the data.
- True
- False
A: False

Q: The sum of the backplane current drawn for all modules in a chassis is used to select the appropriate chassis power supply rating.
- True
- False
A: True

Q: The value of the number stored in I:012 is:
The output display is indicating 77.
- 25
- 30
- 35
- 40
A: 25

Q: The voltage that would be present between the DC common and terminal 4 with the pushbutton closed would be approximately:
- 0 volts.
- 6 volts.
- 12 volts.
- 24 volts.
A: 0 volts.

Q: When a field device contact connected to the input module closes:
- a logic 1 is recorded in the memory location of the coil with the same address.
- a logic 1 is recorded in the memory location of the contact with the same address.
- a logic 0 is recored in the memory location of the coil with the same address.
A: a logic 1 is recorded in the memory location of the coil with the same address.

Q: When SS1 is closed, the time-delay period will be:
- 0 seconds
- 5 seconds
- 10 seconds
- 15 seconds
A: 0 seconds

Q: When the MCR instruction is true, all rung outputs below the MCR will be controlled by their respective input conditions.
- True
- False
A: True

Q: When the sequencer shown is functioning, the circuit increments automatically through the ___________ steps of the sequencer at _________ intervals.
- five, 3 seconds
- six, 3 seconds
- five, 3 minutes
- six, 3 minutes
A: five, 3 seconds

Q: Which instruction, when true, will preset the counter to a count of zero?
- Enter switch input.
- Exit switch input.
- Reset input.
- Lot Full Light output.
A: Enter switch input.

Q: Which module of the PLC is responsible for performing logical operations?
- Processor
- Input
- Output
- Power Supply
A: Processor

Q: Which of the following instructions would most likely be programmed outside the jumped area of a program?
- Latch and unlatch instructions
- Timer and counter instructions
- Immediate inputs and outputs
- Forced inputs and outputs
A: Latch and unlatch instructions

Q: Which one of the following timer parameters represents the value that increments as the timer is timing?
- Accumulated time.
- Preset time.
- Timer address.
- Time base.
A: Accumulated time.

Q: With reference to the circuit and equivalent PLC program, when LS2 is actuated and LS1 is not:
- PLC input I:1/2 is True.
- PLC programmed rung 2 is False.
- pilot light PL2 is ON.
- both a and c.
A: PLC input I:1/2 is True.