SECTION 2 Test

Question 1

The longer time duration that a steady – state exists, the ________the integral action becomes.

Answer 1

greater

Question 2

A system that oscillates is referred to as being ______

Answer 2

unstable

Question 3

The term duty cycle refers to the amount of time a signal is ______ compared to the period of one complete cycle

Answer 3

on

Question 4

By ______ the on – off differential gap, in the cycle time is lengthened.

Answer 4

increasing

Question 5

The output of the derivative function [a] the output of the proportional output when the error signal is getting larger.

Answer 5

?

Question 6

The magnitude of the integral output is proportional to the _____

Answer 6

all provided answers

Question 7

In a PID system, after the derivative function is completed and proportional signal is ineffective the integral function is performed.

Answer 7

TRUE

Question 8

Which section of the closed – loop system performs the four control modes?

Answer 8

?

Question 9

List which type of operational amplifier performs the following PID mode options:

proportional
integral
derivative

Answer 9

?

Question 10

A setpoint change can also produce offset.

T/F

Answer 10

TRUE

Question 11

For a DC variable-speed drive to cause the motor to provide a constant horsepower to the load, it varies the motor’s____ to run it between zero RPM and a base speed, and it varies the ____ to run the motor above the base speed.

options are field strength and arm voltage

Answer 11

arm voltage

field strength

Question 12

Referring to figure 8-7, if the motor speed slows down, the IR voltage at R11 (increase/decrease), causing the SCR’s to fire (sooner/later) in the alternation.

Answer 12

increase

sooner

Question 13

The Armature is the primary part of the motor where an adjustable voltage is connected for speed control.

T/F

Answer 13

True

Question 14

As the motor runs at base speed, the voltage applied to the Armature infield is_____ .

low
moderate
maximum

Answer 14

max

Question 15

The function of Q1 in figure 8-4 is

Answer 15

variable resistance

Question 16

To provide variable torque to a load, the DC variable-speed drive causes the speed of the motor to ___________ when an increase in torque is required.

Answer 16

increase

Question 17

Match the application example with the appropriate motor load classification.

machine tool lathe

pump

hoist

centrifugal fan

extruder

Answer 17

?

Question 18

Which of the following types of circuits are used by the drive controller section?

All provided answers
Regulation
Protection
AC-to-DC converter

Answer 18

all proided

Question 19

By adjusting the DC drive so that the field current is reduced to half, the motor speed _____ .

stays the same

cut off

doubles

Answer 19

doubles

Question 20

Which of the following motor functions can be manipulated by the operator control section?

Starting
Speed
Change of direction
Stopping
All provided answers

Answer 20

all

Question 21

A variable-frequency drive supplies current directly to the _____.

stator
rotor

Answer 21

either stator or answer is both

Question 22

The semiconductor switching device that is used in the inverter section of a PWM drive is the.

bipolar transistor
SCR
IGBT

Answer 22

IGBT

Question 23

The __ oop of the AC closed-loop vector drive provides position information.

Answer 23

Outer

Question 24

By using the programming capabilities of some variable speed drives, it is possible to undersize the .

All provided answers
drive
motor

Answer 24

either drive or all provided answer

Question 25

AC drives cause the speed of an AC induction motor to change by. changing the number of poles varying the armature current varying the bus voltage varying the applied frequency

Answer 25

applied freq

Question 26

Match the following names of the VFD sections with the appropriate circuit function that they perform inverter converter intermediate circuit

Answer 26

converts into simulated sine wave rectifes AC into pulsing DC Filters pulsating

Question 27

Name A method of producing the feed back signal for the following control loops in a vector drive. Speed feedback Current feedback

Answer 27

?

Question 28

The auto boost circuit is used to help accelerate an AC motor when it is starting or running at a low speed. T/F

Answer 28

TRUE

Question 29

One common method of slowing the speed of an AC motor is to reduce the applied voltage. T/F

Answer 29

False

Question 30

The control function of an AC drive is used for stopping the load quickly. braking deceleration speed

Answer 30

deceleration

Question 31

Separation occurs when a mixture is cooled heated both

Answer 31

either both or cooled

Question 32

The value for a standard transmission current signal is _____ when it is zero during calibration.

Answer 32

4 ma

Question 33

In some applications, ingredients can be mixed in a shorter amount of time by

Answer 33

increaseing

Question 34

_____ Thermal energy is supplied to heat exchangers both answers Cold Hot

Answer 34

both

Question 35

Which of the following statements describes the control requirements that must be achieved to ensure product quality? Quantity of raw materials Controlling the process variable during the reaction cycle All provided answers Controlling each step of the sequence

Answer 35

all provided

Question 36

The two functions of a are to convert the output of a _______sensor into a standardized signal and to send a signal to a distant location.

Answer 36

transmitter

Question 37

The purpose of a square root extractor is to___ . Linearize a signal. Multiply the magnitude of a signal remove noise from the signal

Answer 37

multiply magnitude or | linearize a signal

Question 38

A I/P transducer converts ___ to ___

Answer 38

current to pressure

Question 39

The boiling point of a liquid can be increased if the pressure of the container in which it is heated is All provided answers Inverted decreased Increased

Answer 39

increased

Question 40

The characteristics of a sensor refers to the time at which its output reaches a steady state after a signal is applied to the input. static or dynamic

Answer 40

dynamic