TPC 298

Question 1

A programmable logic controller is a device that:

Answer 1

Responds to status changes in a system

Question 2

The memory used for PLC firmware is usually:

Answer 2

Nonvolatile

Question 3

The three main components of a PLC are the programming device, processor unit and:

Answer 3

I/O section

Question 4

Which of the following is a PLC input device?

Answer 4

Proximity sensor

Question 5

The binary system is based on the number ______. The hexadecimal system commonly used with PLC’s is based on the number _____.

Answer 5

2; 16

Question 6

Ladder logic differs from most other computer languages in that it is:

Answer 6

Drawn graphically

Question 7

IN the binary system, each bit has a weight of _______ times the digit to the right of it.

Answer 7

Two

Question 8

The first step in constructing a PLC program is:

Answer 8

Analyzing the process to be controlled

Question 9

Although an output generally appears on only one rung of a ladder logic program, it may be energized by several sets of conditions that appear as:

Answer 9

Branches

Question 10

In ladder logic programming, a ______ symbol is used for input instructions and a ______ symbol is used for output instructions.

Answer 10

Contact; Coil

Question 11

When programming in ladder logic, tags are used to:

Answer 11

Identify a device

Question 12

Which output device is sometimes used as a repeater, using a signal to control several different loads?

Answer 12

Relay

Question 13

If an I/O module supplies current, it is considered a _______ module.

Answer 13

Sourcing

Question 14

To be useful to a PLC, analog input signals must be ______ by an input module.

Answer 14

Digitized

Question 15

Which of the following photoelectric sensors makes use of a reflector placed opposite the device?

Answer 15

Retroreflective

Question 16

Working with accurate, thorough specifications ensures that:

Answer 16

All efforts move towards a common target

Question 17

The most important elements in PLC documentation packages are the:

Answer 17

Hardware drawings and program listings

Question 18

The first step in developing a PLC system to meet given specifications is:

Answer 18

Sizing the system

Question 19

Before turning the newly designed and installed system over to production, use the output disable function and indicating lights to check for correct:

Answer 19

Input wiring

Question 20

The easiest way to develop a PLC program is usually to divide the logic into different:

Answer 20

Tasks

Question 21

A bill of material should include a complete list of part numbers, device numbers cross referenced in the drawing and part:

Answer 21

Manufacturers

Question 22

Which of the following documents walks you through the complete PLC system operation?

Answer 22

Sequence of operation

Question 23

As a good general rule, you should replace the battery in a programmable controller:

Answer 23

Annually

Question 24

Which documentation shows how all field devices are wired and connected to the controller?

Answer 24

Schematic diagram

Question 25

Which of the following is the most common cause of a program problem?

Answer 25

Changes made to the original program

Question 26

Which of the following is a recommended test strategy for troubleshooting?

Answer 26

Start at the switch and test each connection until you reach the controller

Question 27

Moving numbers from one register to another involves the use of a _______ instruction.

Answer 27

Data-handling

Question 28

The speed at which a LAN processes a piece of information is called:

Answer 28

Throughput

Question 29

A LAN application in which information stored in different drops is collected at a central location is known as:

Answer 29

Data acquisition

Question 30

Adding I/O points in an existing rack is called:

Answer 30

Local expansion

Question 31

If local I/O rack cannot accommodate additional I/O modules, you should:

Answer 31

Create a remote I/O rack

Question 32

Which of the following PLC elements gives the system flexibility?

Answer 32

Program

Question 33

When a ladder logic program is written as part of a larger program a ______ is used to tell it when to start its sequence.

Answer 33

Handshaking signal

Question 34

The number of TTL output devices a TTL output module can drive is called:

Answer 34

Fanout