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What size breaker for a 20 horse power motor with 3 phase 208 volts?
Wiki User
∙ 11y ago
The question is impossib;e to answer without knowing the supply voltage.
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What ever the motors full load amperage is, the breaker has to be sized to 250% of that FLA.
Wiki User
∙ 11y ago
Wiki User
∙ 11y agoBreakers and wire size are based on the amperage of the circuit. The following formula is used to find amperage when the HP is known.
HP x 746/1.73 x V x %eff x pf. 20 x 746 = 14920/1.73 x 208 x .86 x .88 = 14920/272 = 54.8 amps.
A standard motor's efficiency between 5 to 100 HP is .84 to .91.
A standard motor's power factor between 10 to 100 HP is .86 to .92.
Conductor sizes for motor loads have to be 125% of the motors full load amps. 54.8 x 125% = 68.5 amps
A #6 copper conductor with an insulation factor of 75 or 90 degrees C is rated at 75 and 85 amps respectively.
A breaker for a motor is sized by 250% of the motors full load amps. 54.8 x 250% = 137 amps. This is not a standard size breaker. The next larger frame breaker size is a 150 amp . Breakers of this size usually have adjustable trips so set the trips at 137 amps.
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Minimum breaker size 60 horsepower motor?
Need motor voltage, amperage and phase to give you an anwer.
How do you use a one phase motor in place of a three phase motor?
To use a single/one phase motor instead of a three phase motor is possible if you have a three phase power supply as you will only need to tap one of the three phases together with neutral and an earthwire, however to use a three phase motor instead of a single phase will require the provision of three phase power supply.
Up to how much HP are single phase motors maufactured?
Horse power is horse power, regardless of what voltages and currents are used. 5 HP single phase is equal to 5 HP 3 phase.
What is the simplest way to run a 3 phase 380 V motor of about 1 KW directly on 220 V single phase supply without resorting to rewinding or frequency converters?
You cannot run a three phase motor on single phase power. You'll burn the motor up within minutes. By the way, I've never seen or heard of a 380 volt motor. Do you mean a 480 volt motor? If so, the only way you can power it is with the correct full voltage and a 3 phase power supply.
Why can a run capacitor with a single phase motor remain in circuit after the motor starts?
Because from the capacitor characteristics at first it will charge and then it will stsrt to run so when the motor get power from single phase capacitor take time for charging. Amit.
Minimum breaker size 60 horsepower motor?
Need motor voltage, amperage and phase to give you an anwer.
What size breaker is used for a 3 horse power motor with 3 phase 208 volts?
I would go with 20 amp 3 pole 15 amp will also do
What would be the horse power required in a 3-phase motor to replace a .5 horsepower single phase motor.?
You still need the same horsepower. The advantage of the three-phase motor is that it will draw lower current.
What single phase motor should you use to get out the same power as a 3 phase one and a half HP motor It's going on a lathe and I don't want to find that a singel phase one and a half motor labors?
One And a Half Horse Power Obviously.
Can you replace a three phase motor 3 Hp RPM 1420 with a single phase motor for a planer?
Probably not. The single phase three horse power motor will be much larger in physical size than its three phase counterpart, and will probably not fit.
How many current needed for the starting of a 5 horse power single phase motor?
120 volt
Which type of the motor is used in fan?
Low-power (a few watts) might use a synchronous motor, most fans use an induction motor. Above a couple of horse-power it might be a 3-phase induction motor.
How is a three phase agricultural motor used when there is no power supply?
With no three phase power supply you can't use a three phase motor of any kind at all!
Can you wire a 3 phase 690 volt delta star motor to 480 volt 3 phase with out harming the motor?
Depends on the motor and the load on that motor. If the motor is loaded to its capacity, it will draw the same amount of power as it would on 690 volts - which will result in ( 690/480 = ) 144% of normal current, which will thermally damage the motor, or will trip overload protection.
How do you use a one phase motor in place of a three phase motor?
To use a single/one phase motor instead of a three phase motor is possible if you have a three phase power supply as you will only need to tap one of the three phases together with neutral and an earthwire, however to use a three phase motor instead of a single phase will require the provision of three phase power supply.
What is the breaker size for a10kw 380v 3 phase power supply?
10amp
Is 3 phase power and 3 pole power the same?
3 Phase power is supplied by a 3 pole supply like a breaker. So essentially yes.
