Title: Chapter 6 Test
Course: Programmable Logic Controls (IC 107-IC 107) > Section: Assessments

Q: A limit switch is usually actuated by:
- hand.
- pressure.
- contact with an object.
- an electromagnet.
A: hand.

Q: A proximity switch can be actuated:
- without any physical contact.
- by a change in light intensity.
- by a change in capacitance.
A: without any physical contact.

Q: Assume that a NC limit switch is substituted for the NO limit switch. For the circuit to operate in the same manner as before:
- the wires to the limit switch would have to be reversed.
- the address of the limit switch would have to be changed to I:1/4.
- the instruction representing the limit switch would have to be changed to an XIO.
- both b and c.
A: the wires to the limit switch would have to be reversed.

Q: For the program shown, what is the address of the instruction associated with the pressure switch?
- I:1/0
- I:1/1
- I:1/2
- I:1/3
A: I:1/0

Q: For the programmed latching operation shown, which two instructions must have the same address?
- On and OFF inputs.
- Latch and unlatch outputs.
- On input and latch output.
- Off input and unlatch output.
A: On and OFF inputs.

Q: If the XIC instruction at address I:1/3 is TRUE:
- output B3:1/3 will also be True.
- output O:2/0 will also be True.
- input I:1/2 will also be True.
- both a and b.
A: output B3:1/3 will also be True.

Q: In general, PLC output modules are designed to switch high current loads directly.
- True
- False
A: False

Q: Latching relays are used when it is necessary for contacts to stay open and/or closed, even though the coil is momentarily energized.
- True
- False
A: True

Q: Most proximity switches come equipped with an LED status indicator to :
- indicate that power is being applied to the switch.
- indicate that the target is within sensing range.
- indicate a blown fuse within sensing range.
- verify the output switching action.
A: indicate that power is being applied to the switch.

Q: Programmed latching circuits are retentive. This means that if power is interrupted the output will __________ when power is returned.
- switch to the ON state
- switch to the OFF state
- remain in its original On or OFF state
- flash ON and OFF
A: switch to the ON state

Q: Rung 1 will be TRUE whenever the:
- pushbutton and limit switch are closed.
- selector switch and pressure switch are closed.
- selector switch and pushbutton are closed.
- pressure switch and pushbutton are closed.
A: pushbutton and limit switch are closed.

Q: Rung 2 will be TRUE whenever:
- the pressure switch is closed.
- the pushbutton is closed.
- the selector switch is closed and rung 1 is True.
- either a or c.
A: the pressure switch is closed.

Q: The abbreviations NO (normally open) and NC (normally closed) represent the electrical state of switch contacts when:
- power is applied.
- power is not applied.
- the switch is actuated.
- the switch is not actuated.
A: power is applied.

Q: The instruction at address B3:1/3 is associated with:
- an internal relay coil.
- an external input device.
- an external output device.
- the solenoid.
A: an internal relay coil.

Q: The Output Latch (OTL) instruction:
- can turn an output on, but it cannot turn the output off.
- is used only to turn a bit on and latch it on.
- allows the output to remain on even if the rung changes to false.
A: can turn an output on, but it cannot turn the output off.

Q: The programmed latching relay instruction is retentive; that is, if the relay is latched it will unlatch if power is lost and then restored.
- True
- False
A: False

Q: The purpose of the M contact shown in the circuit is to:
- open the circuit in the case of a motor overload.
- start the motor from a remote location.
- keep the starter coil energized when the start button is released.
- keep the starter coil de-energized when the start button is released.
A: open the circuit in the case of a motor overload.

Q: The resistor shown in the circuit:
- is called a bleeder resistor.
- is used to power the sensor continuously.
- allows enough current for the sensor to operate but not enough to turn on the input.
A: is called a bleeder resistor.

Q: What is the type of the instruction associated with the selector switch?
- OTE
- OTD
- XIC
- XIO
A: OTE

Q: When both LS1 and LS2 are not actuated:
- PLC program rung 1 is False
- PLC program rung 2 is True.
- pilot light PL2 (O:2/6) is ON.
A: PLC program rung 1 is False