WorksheetsMotor Drive Protection Circuits
Total questions: 8
Worksheet time: 8mins
Name
Class
Date
1.
What type of relay can provide thermal protection for a motor?
a)
Timer relay
b)
Delay relay
c)
Thermal relay
d)
Pushbutton switch
2.
What does an on-delay relay do when it is energised?
a)
Switches immediately
b)
Delays switching
c)
Switches off
d)
Remains unchanged
3.
Which component is used for soft-starting a motor?
a)
Pushbutton switch
b)
Thermal relay
c)
Delay relay
d)
Fuse
4.
What does the thermal protection relay connect to in the motor?
a)
Contactor
b)
Delay relay
c)
Fuse
d)
Thermistor
5.
What is the function of a star contactor in a motor control system?
a)
To switch the motor off
b)
To provide forward operation
c)
To provide reverse operation
d)
To enable soft-starting
6.
What happens to the switches of an off-delay relay when it is de-energised?
a)
Switches immediately
b)
Delays switching
c)
Remains unchanged
d)
Switches off
7.
In the control circuit, what arrangement prevents both forward and reverse contactors from being energised at the same time?
a)
Latch
b)
Interlock
c)
Series
d)
Parallel
8.
Which device is used to protect a motor from overload conditions?
a)
Fuse
b)
Thermal relay
c)
Contactor
d)
Pushbutton switch
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