Chapter 17

Question 1

THe automatic operation preformed by an industrial manufacturing machine is referred to as

Answer 1

Process control

Question 2

Timing functions used to control an operation by industrial manufacturing machines preformed by \_\_\_\_\_\_\_
Ladder logic
Sequential drum controller
Programmable controller
Computers
All above

Answer 2

Al above

Question 3

Which of following industrial operations is referred to as a process
Fluid rate through a pipe
Ingredients filling a vat to a level
Heat applied to a vessel for chem reactions
Vacuum pressure applied to a confined tanks
All above
R

Answer 3

All above

Question 4

T/F

The output signal of a sensor is referred to as the controlled variable

Answer 4

False the output is the measured variable

Question 5

List 3 influences that cause a controlled variable to change

Answer 5

A disturbance appears

Load demands vary

Setpoint are adjusted

Question 6

Dynamic response pertains to
Dead time
Reaction time
Inertia
All above

Answer 6

All above??????

Question 7

T/F

Dead time is influences by the mass of the material from which the controlled variable is made

Answer 7

F??

Question 8

T/F the pure lag of a controlled variable is determined by the quantity and the type of material from which it is made

Answer 8

True

Question 9

One time constant is defined as ____percent of the controlled variable’s change after it is exposed to an energy change

Answer 9

63

Question 10

The dynamic response of a control loop can be improved by ___
Selecting a controller with proper operation
properly tuning a controller
Both

Answer 10

Both

Question 11

TF

The amount at which the final control element turns on in an ON OFF system is proportional to the error signal

Answer 11

False

Question 12

What are 2 household applications that purposely have a deadband to turn a device on and off

Answer 12

Home heating thermostat

Liquid water tank? Steam boiler

Question 13

T/F
The output of the proportional controller moves the final control element to a definite position for each value of the controlled variable

Answer 13

True

Question 14

The avg voltage of a time proportioning controller changes by 5 percent, the ___ will change by___ percent

F

Answer 14

Page 373

Question 15

The proportional ___Setting affects how rapidly the controlled variable changes in response to a step change or load change

Gain
Band
A nd b

Answer 15

Gain

Question 16

A controller with a proportional band of 50 will produce a proportional gain of ____

Answer 16

2

Question 17

When the controlled variable is above the proportional band the proportional action will cause the final control element to be ___
On
Off
Partly on

Answer 17

OFF

Question 18

A controller has more sensitivity if ‘tis proportional band is ___
Narrower
Wider

Answer 18

Narrower

Question 19

What. Condition might occur if a controller is too sensitive

Sluggish response
Excessive cycling
No signal change

Answer 19

Cycling

Question 20

Controller with what kind of control mode elimates offset automatically

Answer 20

Integral?

Question 21

TF tIf the reset rate adjustment on a controller is increaSed the intergal time will____
Increase
Decrease
Stay same

Answer 21

Decrease

Question 22

A reset rate of 10 repeats per minute equals an integral time of ___minutes per reapet
R

Answer 22

6 seconds

Question 23

What kind of controller action is related to the rate at which an error develops

Answer 23

Derivative

Question 24

While tT/F

The derivative mode is recommended in applications where the controlled variable lags behind the change of the final control element

Answer 24

False

Question 25

When tuning a cascade control system with 2 loops, which loop should be tuned first
Primary
Secondary

Answer 25

Secondary

Question 26

Which of the following terms describes a control strategy in which the output of one controller is used to maninpulate the setpoint of another controller
Ratio
Cascade
Feed forward
Adapative

Answer 26

Cascade

Question 27

The ___ controller in a cascade system revceives the signal that represents the condition of the controleld variable
Prime
Sec

Answer 27

Primary

Question 28

IN a cascade system, the _____ loop is consider the primary loop
Inner
Outer

Answer 28

Outer

Question 29

Which of the following statements are true about feed forward control (more than one answer possible)

Should be used with feedback control
Can compensate for unmeasurable disturbs
Outsputs casues manipulated variable to change
Improves speed at which corrections are made

Answer 29

Should be used with feedback control and

Page 388?

Question 30

Which of the following is true

Feedforawrd control is based on observing changes in the controlled variable and then adjusting he manipulated variable to compensate

Feed forward control helps to prevent changes in the controlled variable before they occurs

Answer 30

FBoth true

Question 31

T/F

When 2 or more ingredients are blended in a mixer the flow of each one is controlled by a ratio control system

Answer 31

True

Question 32

A strategy in which the flow rate of one fluid stream is maintained at some proportion to the flow rate of another fluid stream is
Cascade
Feedback
Ration control
Adapative

Answer 32

Ratio control

Question 33

T/F

Wild flow ingredient in ration control is measured

Answer 33

True

Question 34

In ratio control the reference flow rate is referred to as ___ flow

Answer 34

Wild

Question 35

An adaptive controller sues a combo of software programming and microelectronics to compensate for ___easurements
Linear
Non linear

Answer 35

Non linear

Question 36

Which of the following process measurements produce a non linear signal…more than one

Differential pressure flowmeter
Ultrasonic level meter
PH of a. Solution
None of absolve

Answer 36

Differential pressure

PH of solution