Question 1

A bleeder resistor can be connected to drain off unwanted module leakage current.

Accepted Answer

A) True 
 B)False

Question 2

Which function of a PLC would be used to view the transition history (on or off states) of a bit(s)?

Accepted Answer

A) Change radix 
B) Forcing 
C) Cross-reference 
D) Contact histogram

Question 3

It is rare for sensors and actuators connected to the I/O of the process to fail.

Accepted Answer

A) True 
 B)False

Question 4

A properly installed grounding system is designed to provide a high-impedance path to earth ground.

Accepted Answer

A) True 
 B)False

Question 5

A good location for a PLC enclosure is close to:

Accepted Answer

A) the machine or processor. 
B) large AC motors. 
C) high-frequency welders. 
D) annealing furnaces.

Question 6

Protective ground wires must have a resistance value of less than one ohm.

Accepted Answer

A) True 
 B)False

Question 7

Hardwired MCRs are used to interrupt power to the I/O rack.

Accepted Answer

A) True 
 B)False

Question 8

The suspend instruction is used to trap and identify specific conditions.

Accepted Answer

A) True 
 B)False

Question 9

When routing power and I/O signal wiring to and within a PLC enclosure, you should:

Accepted Answer

A) use the shortest possible wire runs for I/O signals. 
B) never run signal and power wiring in the same conduit. 
C) run low-level signal conductors as shielded twisted pair. 
D) all of these.

Question 10

A fiber optic wired control system is most susceptible to electrical noise.

Accepted Answer

A) True 
 B)False

Question 11

Certain input field devices may have a small leakage current when they are:

Accepted Answer

A) in the on state. 
B) in the off state. 
C) examined for an on condition. 
D) examined for an off condition.

Question 12

Leakage current can falsely activate a PLC input.

Accepted Answer

A) True 
 B)False

Question 13

In Allen-Bradley controllers, RSLinx software is needed to set up the communication path between the PLC processor and the personal computer (PC).

Accepted Answer

A) True 
 B)False

Question 14

I/O leakage problems usually occur with devices that use:

Accepted Answer

A) solid-state switching circuits. 
B) hard contacts. 
C) noise-suppression circuits. 
D) voltage-suppression circuits.

Question 15

Which of the following would not normally be located within the PLC enclosure?

Accepted Answer

A) I/O modules 
B) Limit switch 
C) Master control relay 
D) Isolation transformer

Question 16

To make sure that equipment does not operate while PLC maintenance is conducted, lockout and tagout devices must be in use.

Accepted Answer

A) True 
 B)False

Question 17

Editing a PLC program normally refers to:

Accepted Answer

A) replacement of an existing program. 
B) monitoring of an existing program. 
C) making changes to an existing program. 
D) all of these.

Question 18

Program addressing conflicts can be caused by:

Accepted Answer

A) using the same address for two outputs. 
B) faulty wiring. 
C) faulty connections. 
D) scan time period.

Question 19

The first step in troubleshooting is to:

Accepted Answer

A) identify or describe the faulty operation. 
B) test the process field devices. 
C) test the wiring. 
D) test the I/O modules.

Question 20

A driver is a computer program that controls a device.

Accepted Answer

A) True 
 B)False

Exam 10: PLC Installation Practices, Editing, and Troubleshooting

A bleeder resistor can be connected to drain off unwanted module leakage current.

Which function of a PLC would be used to view the transition history (on or off states) of a bit(s) ?

It is rare for sensors and actuators connected to the I/O of the process to fail.

A properly installed grounding system is designed to provide a high-impedance path to earth ground.

A good location for a PLC enclosure is close to:

Protective ground wires must have a resistance value of less than one ohm.

Hardwired MCRs are used to interrupt power to the I/O rack.

The suspend instruction is used to trap and identify specific conditions.

When routing power and I/O signal wiring to and within a PLC enclosure, you should:

A fiber optic wired control system is most susceptible to electrical noise.

Certain input field devices may have a small leakage current when they are:

Leakage current can falsely activate a PLC input.

In Allen-Bradley controllers, RSLinx software is needed to set up the communication path between the PLC processor and the personal computer (PC).

I/O leakage problems usually occur with devices that use:

Which of the following would not normally be located within the PLC enclosure?

To make sure that equipment does not operate while PLC maintenance is conducted, lockout and tagout devices must be in use.

Editing a PLC program normally refers to:

Program addressing conflicts can be caused by:

The first step in troubleshooting is to:

A driver is a computer program that controls a device.