Question 1

A controller's ____ determines how well it responds to changes in motor performance and is usually expressed as a percentage.

Accepted Answer

A)   set point
B)   regulation
C)   efficiency
D)   feedback B

Question 2

Motor operation in quadrant ____ produces regenerative braking action when the motor turns in reverse.

Accepted Answer

A)   1
B)   2
C)   3
D)   4 D

Question 3

Armature voltage control is the type most commonly used in DC drives.

Accepted Answer

A) True 
 B)False  True

Question 4

In which quadrant of motor operation is the motor regenerating?

Accepted Answer

A)   Quadrant 1
B)   Quadrant 2
C)   Quadrant 3
D)   Quadrant 4

Question 5

If the motor doesn't run, the problem must be the drive.

Accepted Answer

A) True 
 B)False

Question 6

The most common cause of motor failure is heat.

Accepted Answer

A) True 
 B)False

Question 7

Open-loop control is also called automatic control.

Accepted Answer

A) True 
 B)False

Question 8

Which circuit is adjusted to detect certain levels of electrical interference or "noise," and trips the drive in the event of a voltage sag, spike, or single phasing?

Accepted Answer

A)   Watchdog circuit
B)   Oscillator circuit
C)   Shunt field circuit
D)   Low-voltage logic circuit

Question 9

A command signal, sometimes called the ____ or reference signal, is programmed into the DC drive and sets the desired operating speed of a DC motor.

Accepted Answer

A)   steady state
B)   target
C)   set point
D)   encoder

Question 10

In which quadrant of motor operation is the motor driving a load and turning in the forward direction?

Accepted Answer

A)   Quadrant 1
B)   Quadrant 2
C)   Quadrant 3
D)   Quadrant 4

Question 11

A ____ is a circuit that uses very fast electronic switches.

Accepted Answer

A)   booster
B)   stepper
C)   modulator
D)   chopper

Question 12

The control section of a DC drive uses three types of signals to evaluate motor performance: the command, feedback, and ____ signals.

Accepted Answer

A)   set point
B)   reference
C)   error
D)   open-loop

Question 13

An electronic variable speed drive has two basic sections: the control section and the power section.

Accepted Answer

A) True 
 B)False

Question 14

Most drive failures occur in the ____ section, where you will find power SCRs, transistors, MOSFETs, and so on.

Accepted Answer

A)   power
B)   control
C)   feedback
D)   transistor

Question 15

Mechanical vibration may loosen the mounting or alter the ____ of feedback devices.

Accepted Answer

A)   input
B)   alignment
C)   adjustment
D)   control

Exam 22: Dc Electronic Variable Speed Drives

A controller's ____ determines how well it responds to changes in motor performance and is usually expressed as a percentage.

Motor operation in quadrant ____ produces regenerative braking action when the motor turns in reverse.

Armature voltage control is the type most commonly used in DC drives.

In which quadrant of motor operation is the motor regenerating?

If the motor doesn't run, the problem must be the drive.

The most common cause of motor failure is heat.

Open-loop control is also called automatic control.

Which circuit is adjusted to detect certain levels of electrical interference or "noise," and trips the drive in the event of a voltage sag, spike, or single phasing?

A command signal, sometimes called the ____ or reference signal, is programmed into the DC drive and sets the desired operating speed of a DC motor.

In which quadrant of motor operation is the motor driving a load and turning in the forward direction?

A ____ is a circuit that uses very fast electronic switches.

The control section of a DC drive uses three types of signals to evaluate motor performance: the command, feedback, and ____ signals.

An electronic variable speed drive has two basic sections: the control section and the power section.

Most drive failures occur in the ____ section, where you will find power SCRs, transistors, MOSFETs, and so on.

Mechanical vibration may loosen the mounting or alter the ____ of feedback devices.