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What circuit breaker rating do you need for a 3 phase electric motor?
Wiki User
∙ 14y ago
The circuit breaker is sized to the full load amps of the motor times 250%.
Wiki User
∙ 14y ago
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What is Selection procedure for motor protection circuit breaker?
The selection of overload protection for motors is taken from a table in the electrical code book. It is based on the full load current rating of the motor.
Cause of a circuit breaking tripping?
Tripping is caused by excessive current, which is usually the result of a fault in cable or equipment. The circuit breaker is there for safety and it trips to prevent a possible fire starting.
How do you choose circuit breaker all the control circuit if i have 50kw power of motor?
The breaker should be sized to 250% of the motor's full load amperage.
What is the reason if you are running an electric motor with a star delta starter but whenever it is switched to delta at the same instant its circuit breaker trips?
Check your Delta connections first if the phases is corresponding, and check your Circuit Breaker if it sufficiently rated.
What causes electrical overloads?
Electrical overloads are caused by the load amperage increasing above what it should normally be. On a motor load this could be a request for the motor to do more work than the motor is capable of, working outside of its HP rating. In a house circuit an overload is created by plugging more devices into the circuit than the circuit breaker can handle. Again the load current will be higher than the circuit will allow and the circuit will open by the tripping of the breaker.
What size breaker do you use for a furnace?
It depends on the rating of the furnace. There should be a plate or sticker somewhere on the furnace that shows the rating. If you are just powering a blower motor the rating will be lower than if you have an electric heating element.
What device close or breaks the circuit?
There are a number of devices that break a circuit. On motor circuits an overload block opens the circuit when the motor's current goes above the motor's nameplate rating. Likewise a fuse or a breaker will open a circuit when the current goes above their rated limit. In home wiring circuits the home devices are controlled by a simple on- off switch. Electric heating circuits are controlled by thermostats that regulate the heaters by opening and closing the heater's supply voltage.
What happens when both 110v leads are applied to one side of a 220v electric motor?
The breaker will blow because you are effectively causing a short circuit.
What is the circuit for reversing an electric motor?
I HAVE A SMALL ELECTRIC CLOCK MOTOR THAT I NEED TO REVERSE. WHAT IS THE CIRCUIT I NEED TO REVERSE IT?
What is the formula to calculate the fuse or circuit breaker to protect motors?
Motors are rated either in Watts or Amps, and by Voltage. If the motor is rated in Amps, that is the fuse or circuit breaker size you will need. If rated in Watts, you will have to use the formula P=IE, where P is power in Watts, I is current in Amps, and E is Electromotive Force in Volts. Since we know the watts and volts, we solve for current, thus: I=P/E, and I will be your current rating. One note: These calculations give the MINIMUM rating needed for the motor to run. Fuses and circuit breakers are usually designed so that they will break if the circuit pulls 250% of the Motor's rating.
What happen if the window is not going up or down?
One window, probably the switch or the electric window motor. All windows, probably the fuse or circuit breaker.
What is a 30 amp circuit breaker used for?
A 30 amp circuit breaker is needed unless the load is a motor circuit, then it has to be sized to 250 percent of the motors full load amps. For 30A circuit is needed breaker 30*1.25=37.5 --> 40A. If load is lamp or heater, then use breaker of group A or B. If load is motor, then use breaker of groupC or D (very hard start) or special safe breaker for motor - with variable amp setpoint. See related link also. By code you are only allowed 80% of the rating of a breaker. So 30x80%=24amps. 24 amps is the MAX allowed on a 30 amp breaker. You would need a 40amp breaker for a 30 amp circuit. 40x80%=32. So you would want a double pole 40amp breaker.
