answersLogoWhite

0


Best Answer

A motor that is rated at 250 full load amps will need 400 amp time delay fuses or a 500 amp frame breaker with adjustable amperage trips. The wire size for this motor has to be 125% of the motors FLA. 250 x 125% = 312 amps. A 350 MCM copper conductor with an insulation factor of 90 degrees C is rated at 325 amps.

User Avatar

Wiki User

10y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What is the circuit breaker rating required for a motor with a 250 Ampere full load current?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Continue Learning about Engineering

What are the breaker ampere trip ratings?

The ampere frame rating for a circuit breaker designates how the circuit breaker should be configured. It also states the trip unit of the amp.


What is the proper ampere rating of circuit breaker for electric arc welder?

The proper ampere rating of a circuit breaker for an electric arc welder depends on the arc welder. Each is different. Look at the nameplate on the arc welder and choose the circuit breaker and wiring accordingly.


What is the charge flowing per second in a circuit?

The numerical representation of one coulomb of charge moving past a point in a circuit per second is called an ampere.


What is the Electrical circuit breaker making and making capacity?

making current is a peak value attain at first cycle when the circuit breaker is close.the making current rating is expressed in "peak" value of the maximum ac current it can safely close on that's why it is always have higher value than breaking current. Making current is limited by the withstand capability of the contacts. Breaking current is based on the ability of the contacts to interrupt the current. If the contacts are not able to interrupt the current when they open, the heat energy in the resulting arc will often destroy the device. the breaking current rating is expressed in RMS value of the current.


What meaning circuit breaker 400af 300 at?

The "AF" stands for the Frame Ampere rating, so in this case will be 400 Amp Frame. The "AT" stands for Trip Ampere rating, and in this question will be 300 Amp Trip.

Related questions

What are the breaker ampere trip ratings?

The ampere frame rating for a circuit breaker designates how the circuit breaker should be configured. It also states the trip unit of the amp.


What is the minnimum size equipment grounding conductor required by the NEC for a branch-circuit protected by a 50-ampere rated circuit breaker?

#10 copper


What is the difference of Ampere Frame and Ampere Trip of Circuit Breaker?

Hi AF Ampere Frame Maximum Long Time current available in the physical package of CB AT - Ampere Tripping long time trip setting of the CB Nishantha DCL


What is the proper ampere rating of circuit breaker for electric arc welder?

The proper ampere rating of a circuit breaker for an electric arc welder depends on the arc welder. Each is different. Look at the nameplate on the arc welder and choose the circuit breaker and wiring accordingly.


What happen when a fuse wire of 100 ampere is used when a circuit at home draws a maximum current of 20 ampere?

The fuse or breaker should be no bigger than specified for the wiring and devices on the circuit. Your nominal current draw may be 20 amps, but a short circuit would cause maximum current to flow which in this case would be 100 amps until the fuse blew.


What are unit amps?

An "ampere" is a measure of the current in an electrical circuit.


What is the meaning ampere protection?

Amperes refer to the current in an electrical circuit. Ampere protection is rarely used but it refers to current protection. Typically this will relate to protection against over current events with fuses or circuit breakers.


What is the charge flowing per second in a circuit?

The numerical representation of one coulomb of charge moving past a point in a circuit per second is called an ampere.


What job does the ammeter do in the circuit?

The ammeter measures the amount of current in a circuit.


What is the Electrical circuit breaker making and making capacity?

making current is a peak value attain at first cycle when the circuit breaker is close.the making current rating is expressed in "peak" value of the maximum ac current it can safely close on that's why it is always have higher value than breaking current. Making current is limited by the withstand capability of the contacts. Breaking current is based on the ability of the contacts to interrupt the current. If the contacts are not able to interrupt the current when they open, the heat energy in the resulting arc will often destroy the device. the breaking current rating is expressed in RMS value of the current.


For circuit breaker what does it mean by AF AT?

AF refers to the ampere rating of the breaker frame and AT refers to the breaker trip rating in amps. These are not breakers that you would find in your home but industrial molded case breakers. The current trips can be changed out to different values all within the same frame size.


What is the current in circuit with 6 v battery and 2 resistor?

3 ampere