WorksheetsMotor Protection and Sizing Standards
Total questions: 15
Worksheet time: 15mins
what article deals with OL protection of continuous duty motors
430.52
430.22
430.32
430.110
According to the NEC. the max fault protection using a inverse time trip breaker and feeding a squirrel cage motor is
(a)
Motor conductors shall be sized no less than (a) of the NEC FLC
Refer to article 430.110. Disconnects have to be sized to at least (a) of the motors FLC
Refer to article 430.102. Motor disconnecting means shall be located (a)
what is the FLC of a 75 HP motor fed with 208vac
(a)
what is the FLC of a single phase 10 Hp motor fed with 230vac?
(a)
what is the proper Nema Size starter for a 75 HP motor fed with 480 VAC
(a)
what is the required wire size to feed following motor
HP-30
Voltage - 230
FLA-78
Amb.-40C
SF. 1.35
(a)
what size fuse would be adequate to use as fault protection for a 75 HP 3 phase motor fed with 480vac?
(a)
If a motor is less than 1 HP and automatically started, OL protection is not required.
TRUE
FALSE
if a motor is less than 1 HP and manually started and permanently installed It must have OL protection in accordance with 430.32
TRUE
FALSE
What is the required NEMA Size MS for a 150 HP motor fed with 480 VAC
(a)
what is the NEC definition of a Continuous Duty rated Motor
Motor capable of short run times
Motor running for more than 3 hours
Motor running for 60 minutes or more
Motor rated to run at Full rpms for more than 6 minutes
Why is Fault protection sized differently than OL protection? Please Explain
