Chapters 35&36

Question 1

Impedance is the opposition to the potential that moves material or energy in or out of a process.

Answer 1

True

Question 2

A step change is a sudden change in an input variable in a process that is managed by a controller.

Answer 2

True

Question 3

A time constant (t) is the measured time when an output response is 1.00 or 100% of an input step change.

Answer 3

False

Question 4

Dead time is a delay in the response of a process that represents the time it takes for a process to respond completely when there is a change in the inputs to the process.

Answer 4

False

Question 5

Capacitance is the ability of a process to store material or energy.

Answer 5

True

Question 6

Lag time is the period of time that occurs between the time a change is made to a process and the time the first response to that change is detected.

Answer 6

True

Question 7

An _ reaction is a chemical reaction that generates heat during the reaction and increases temperature.
A. Endothermic
B.Exothermic
C. Enthalpic
D. Entropic

Answer 7

B

Question 8

An _ reaction is a chemical reaction that consumes heat, and more heat energy must be added to sustain the reaction.
A. Enthalpic
B. Entropic
C. Endothermic
D.Exothermic

Answer 8

C

Question 9

A(n) _ curve is a plot of the PV against the CV.
A.Open loop
B. Process
C. Closed loop
D. Gain

Answer 9

B

Question 10

A _ variable is an independent variable in a process control system that is used to adjust a dependent variable.
A. Control
B. Setpoint
C.Dynamic
D. Controller

Answer 10

A

Question 11

A primary element is the sensing device that detects the condition of a _ variable.
A. Control
B. Process
C. Setpoint
D. Secondary

Answer 11

B

Question 12

A _ variable is a dependent variable that is controlled in a control system.
A. Manipulated 
B. Control
C. Process
D. Static

Answer 12

C

Question 13

_____ is the equipment and techniques used to automatically regulate a process to maintain a desired outcome.

Answer 13

Automatic Control

Question 14

_____ is the ratio of the change in output to the change in input of a process.

Answer 14

Gain

Question 15

A(n) _____ process is a process where the gain at any point of the input range is the same as the gain at any other output.

Answer 15

LInear

Question 16

Proportional gain is the gain, or sensitivity, of a control variable.

Answer 16

True

Question 17

A proportional (P) control strategy is a method of changing the output of a controller by an amount proportional to the error.

Answer 17

True

Question 18

ON/OFF control is a method that produces an output that provides only an ON or OFF signal to the final element of the process.

Answer 18

True

Question 19

The reset rate is the reciprocal or integral time

Answer 19

True

Question 20

ON/OFF proportional control is proportional control combined with both integral control and derivative control.

Answer 20

False

Question 21

A(n) \_\_ output is an output that has a continuous range of possible output values between minimum and maximum limits.
A. Digital
B. Discrete
C. Analog
D. Binary

Answer 21

B

Question 22

\_\_\_ is the range of values of an input that corresponds to a full range of output from a controller, stated as a percentage.
A. Proportional band
B. Throttling range
C. Proportional Gain
D. Integral Gain

Answer 22

A

Question 23

\_\_\_ is a controller function that positions a final element in a central position when the process variable is at setpoint.
A. Overshoot
B. Integral gain
C. Proportional gain
D. Output Bias

Answer 23

D

Question 24

\_\_\_ is the change of the PV that exceeds the upper deadband value when there is a disturbance to the system.
A. Undershoot
B. Gain
C. Overshoot
D. Tuning

Answer 24

C

Question 25

``` A(n) __ is the range values where a change in measurement values results in no change in controller output. A. Proportional band B. Lag C. Open loop D. Deadband ```

Answer 25

D

Question 26

``` __ control is a control strategy that only controls the inputs to a process without feedback from the output of the process. A. Feedback B. Feedforward C. Proportional D. ON/OFF ```

Answer 26

B

Question 27

A(n) ____ ON/OFF controller is an ON/OFF controller that has a predetermined output period during which the output contact is held closed for a variable portion of the output period.

Answer 27

Time Proportional

Question 28

___ is the change of the PV that goes below the lower deadband value when there is a disturbance into the system.

Answer 28

Undershoot

Question 29

___ is the number of units of a process variable that causes an actuator to move through its entire range.

Answer 29

Throttling range

Question 30

``` List and describe three components of a control loop: 1. 2. 3. Descriptions ```

Answer 30

1.Controller Device that compares a process measurement to a setpoint and changes the control variable to ring back the PV to the setpoint. 2. Proportional Variable (PV) Dependent variable that is to be controlled in a system. 3. Control Variable (CV) Independent variable in the process control system to adjust to dependant variable.

Question 31

List two types of chemical reactions and tell the difference. 1. 2. Descriptions

Answer 31

1. Exothermic- releases heat and let's things expand | 2. Endothermic heat- conserves heat and make things condense.

Question 32

What is the difference between an Open and Closed loop?

Answer 32

Open loop doesn't get feedback. | Closed loop does get feedback. Open loops let's electricity flow easily closed loop does not.

Question 33

What is the abbreviation, formula, and description of gain. Abbreviation: Formula: Description:

Answer 33

``` Abbreviation: K Formula: K=Input _________ Output Description: Gain is how sensitive the product is to the variations of change in the process. ```

Question 34

What are the two controller actions and the difference between them?

Answer 34

Direct- PV increase and CV increases | Reverse- controller action where the controller output decreases and the Process variable measurement increases.

Question 35

List and define the three process dynamics: 1. 2. 3.

Answer 35

1. Lag- A delay in response of a process that represents the time it takes for a process to respond completely when there is a change in the inputs to the process. 2. Deadtime- The period of time that occurs between the time change is made to a process and the time the first response to that change is detected. 3. Gain- A ratio of the change in output to the change in input of a process.

Question 36

What is Deadband?

Answer 36

Deadband- | The range of values where a change in measurement value does not result in a change in controller output.

Question 37

What is Proportional Band?

Answer 37

Proportional Band- | The range of input values that corresponds to a full range of output from a controller, stated as a percentage%.

Question 38

What is the difference between a step change and a load change?

Answer 38

Step Change- A sudden change in an input variable in a process that is managed by a controller. Load Change- A change in process operating conditions that changes the process variable (PV) and must be compensated for by a change in the control variable (CV)

Question 39

What is Output Bias, and what is the most common output bias?

Answer 39

Output Bias- | A controller function that positions a final element in a central position when the process variable is at setpoint.

Question 40

Explain Transmitter Dynamic Gain:

Answer 40

Transmitter Dynamic Gain- | The amount of output change from a transmitter for a specific input change.

Question 41

What is the difference between Controller Gain and Proportional Gain?

Answer 41

Controller Gain- The gain, or sensitivity of a controller itself. Proportional Gain- The gain or sensitivity of a proportional term only.