How many amps does a 2 hp 240 volt single phase motor draw?

Answer 1

One horsepower electric is defined as 746 watts, so two horsepower is 1492 watts. Divide that by 240 volts, and you get about 6.2 amperes. Now you have to consider the power factor, which is the ratio of apparent power to true power, caused by the inductive (reactive) load of the motor causing the current to be out of phase with respect to voltage. You did not say what the power factor was, so lets assume it is 0.8. That makes the current about 7.75 amperes.

That's running current, at full load. Starting current is often four times higher. The NEC list this motor has drawing 12 amps and to wire this motor you would use this value, unless the actual nameplate amps on the motor was higher.

Answer 2

It is best to use the nameplate amperage for accuracy. The code book says it is 8 amps at 230 volts.

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on a single phase , LINE x with NEUTRAL. to acquire amps. you divide wattage by voltage to get INTENSITY = AMPS. 1 hp equals 746 watts divided by voltage 240 = 3.10 AMPS

Answer 3

One horsepower electric is defined as 746 watts. Two horsepower, then, is 1512 watts. Divide that by 120 volts, and you get 12.6 amperes.

However, there is a thing called power factor, which is the ratio of apparent power over true power. It is due to the fact that in a inductive (or capacitive) load, i.e. a reactive load, the current is not in phase with the voltage. If it were in phase, such as for a resistive load like a toaster, then power factor would be 1, but for a motor, it is not.

Power factor is the cosine of the phase angle between voltage and current. It depends on many things, including motor design, actual operating voltage, and load. The question does not say what the power factor is, so let's assume a power factor of 0.8, which corresponds to a phase angle of -37 degrees.

So divide 12.6 amperes by 0.8 and you get 15.75 amperes.

If you are sizing a branch circuit for this motor, you must include 25% reserve capacity (depending on your particular electrical code), so that 15.75 amperes becomes 19.7 amperes. Lets call it 20 amperes.

In addition, motors take about four times their running current to start, so your branch circuit needs to support a short term overload of 80 capacity of amperes.

All of that said, the real criteria is what is written on the nameplate of the motor. That takes precedence over any calculation you might make.

<<>> Current is variable on electric motors. On a 240 v system you should allow 7 amps per HP. So for a 2 HP motor on 120v the current allowance is 28 amps.

Answer 4

Probably 6-8 amps.

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For calculation purposes the electrical code book recommends using 8 amp at 230 volts. For sizing conductors and breakers to use on this motor, the motor's actual nameplate reading should always be used first. Keep in mind that the conductors have to be sized to 125% of the motors nameplate rating and breakers should be sized for 250% of the motor's nameplate rating.

Answer 5

6 amps