Test

Question 1

Define a programmable logic controller

Answer 1

A solid-state device capable of storing instructions, such as sequencing, timing, data manipulation, and communication

Question 2

In the early years of their existence, PLC’s were primarily used for

Answer 2

On off control

Question 3

The ____ and the _____ are the two basic sections of the programmable controller

Answer 3

CPU, I/0 interface

Question 4

The input/output system forms the interface through which field devices are connected to the controller

Answer 4

True

Question 5

The ladder program in a PLC is _________ inside the PLC’s CPU

Answer 5

Soft wired

Question 6

Programmable controllers can be used to diagnose field device malfunctions

Answer 6

True

Question 7

The most common binary codes are

Answer 7

ASCII
BCD
Gray

Question 8

Why is the binary number system used in digital devices such as programmable controllers and computers?

Answer 8

It is easier to design machines that distinguish between only two entities or numbers like zero and one

Question 9

In binary one plus one equals

Answer 9

One-zero

Question 10

Defined the following
Bit
Nibble
Byte
Word

Answer 10

1 digit
4 bits
8 bits
One or more bytes

Question 11

A word can be three bites long

Answer 11

True

Question 12

Which logic type is more conventional

Answer 12

Positive logic

Question 13

The logic functions used in PLCs include

Answer 13

All of the above

Question 14

Ladder diagrams are also called contact symbology

Answer 14

True

Question 15

Each symbol in a PLC ladder rung has a ____ by which a connect device is referenced

Answer 15

All of the above

Question 16

The three components that form the central processing unit are

Answer 16

Processor, memory system, and power supply

Question 17

The CPU encompasses all the elements that formed the intelligence of a PLC system

Answer 17

True

Question 18

Software instructions that allow the interruption of a scan to receive inputs or to update outputs are known as

Answer 18

Immediate instructions

Question 19

Parity check is sometimes called

Answer 19

Vertical redundancy check

Question 20

PLCs cannot use input voltages from a DC source

Answer 20

False

Question 21

Name the two most common programming devices used with programmable controllers

Answer 21

Mini programmer and personal computer

Question 22

The total memory system in a POC is composed of the _________ and the ________ memories

Answer 22

Executive and application

Question 23

________ is the most commonly used application memory and is generally backed up by a battery

Answer 23

RAM

Question 24

The executive and scratchpad areas are part of the

Answer 24

System memory

Question 25

The user program memory is reserved for the storage of the

Answer 25

Control logic

Question 26

An address can be used as many times as needed in the control program

Answer 26

True

Question 27

Isolated AC/DC I/O modules operate like standard AC/DC modules, except that each input and output has a separate comment or return line

Answer 27

False

Question 28

A master rack refers to an enclosure that contains

Answer 28

The processor

Question 29

The address of an I/oh device, which depends on its terminal connection and interface placement in the rack , identifies the device in the control program

Answer 29

True

Question 30

A logic one signal indicates that a field device is on while a logic zero signal indicates that a device is off

Question 31

Name the two sections of an AC/DC input modules input circuit

Answer 31

Power section and logic section

Question 32

A thumb wheel switch provides information to the PLC in ______ format

Answer 32

BCD

Question 33

Give two examples of output devices that interface with register output modules

Answer 33

Small DC loads and 7 segment display

Question 34

Analog interfaces are used in applications, requiring measurements and control of continuous signal

Answer 34

True

Question 35

Analog interfaces, except either unipolar or bipolar types of voltages

Question 36

The most common formats used to represent analog values in a PLC are _______ and ______

Answer 36

Binary and BCD

Question 37

Analog interfaces can have either single ended( All comments tied together) or differential (all commons separate)

Question 38

Numerical data received at the module from the processor is converted into an analog voltage or current using a

Answer 38

D/AC

Question 39

Some PLCs are arithmetic instructions to access or send data to analog interfaces

Answer 39

True

Question 40

Functional blocks are a part of basic ladder language

Answer 40

False

Question 41

The programming language they use and or and NOT logic functions to implement the control program is called

Answer 41

Boolean

Question 42

The left side of a PLC ladder diagram simulates the L1 powerline

Answer 42

True

Question 43

How is a latched coil condition reset

Answer 43

Through a unlatch output instruction

Question 44

For up counter increments, it’s counted value each time it’s referenced event makes a position change of

Answer 44

Off to on