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There are two ways: If the amps are the same on all three phases (voltspp is the phase to phase voltage): amps * voltspp * 1.73 = watts If the amps are different on each phase (voltspn is the phase to neutral voltage): (ampsA + ampsB + ampsC) * voltspn = watts In a 480V system, 480 is phase to phase and 277 is phase to neutral, likewise 208/120, etc. Example - 12A on all phases, 480/277V system: 12 * 480 * 1.73 = 9965W Example - phase A = 4A, phase B = 6.3A, phase C = 2.2A, 208/120V system: (4 + 6.3 + 2.2) * 120 = 1500W

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15y ago
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12y ago

It really doesn't matter whether the system is single-phase or three-phase, if you know the power, the rate of supplying energy, then you can work out the amount of energy supplied. If the power (in watts) is constant, then the energy supplied (in watt hours) is determined simply by multiplying that power by the time for which energy is supplied. To determine kilowatt hours, power in watts must be converted to kilowatts, and time converted to hours. It's more complicated if the power is continually changing!

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11y ago

You convert W into VA by dividing by power factor and efficiency. You then divide by three to get power per winding. You then divide by voltage per winding to get current per winding. If you are star connected, you are done. If you are delta connected you multiply by 1.732 to get current per line.

Example: 10 HP motor running on 460 delta, pf 0.92 ef 0.95. 746 W / HP times 10 HP is 7.46 kvA 7.46 kVA / 0.92 pf / 0.95 ef is 8.54 kVA. 8.54 kVA divided by 3 is 2.88 kVA per winding. 2.88 kVA per winding divided by 460 volts is 6.19 amperes.

A ten HP motor could well run on delta, so the answer could be 6.19 amperes per phase. If the motor runs star-delta, you multiply 6.19 by 1.732 to get 10.7 amperes per phase delta.

The same philosophy applies to other loads, such as lighting loads, heaters, UPS's, and Arc Welders.

Alternative Answer

The expression for power in a balanced three-phase system is as follows,

P = 1.732 EL IL x power factor

...where EL and IL represent the line voltage and line current, respectively.

You simply manipulate this equation to make IL the subject. For unbalanced loads, it is far more complicated!

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13y ago

3 phase power = I * V(L-L) * sqrt(3)

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Q: How do you convert watts in to kwh in three phase system?
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How many watts is 4.75 amp refrigerator starting watts?

To convert amperage to watts, you need to know the voltage, power factor, and the number of phases that you are working with. For a residential refrigerator this is single phase, an industrial refrigerator could be three phase.


How you convert the value of single phase power to value of 3 phase power?

Electric power is measured in watts. It does not matter if it is single phase or three phase. All things being equal, for the same load, the power measured in a single phase circuit or a three phase circuit, will be the same.


How do you convert 440 Amps to KVA for three phase system?

You must rephrase your question to make it more specific. <<>> The formula to use to find KVA in a three phase system is, KVA = Amps x Volts x 1.73/1000.


How do you convert single phase kva to three phase kva?

Va=volts x amps. The K stands for one thousand. So 1 Kva is one thousand watts. So 415v times 120a= 49,800 what's. You divide that by a thousand and you get 49.8. So it would be 49.8 Kva.


Convert newtons to watts?

to convert watts into meters


How do you convert arms to watts?

convert arms to watts


How to Calculate three phase watts with unbalanced phase current?

You will need to determine the power per phase, and add them up to give the total power of the three-phase load. To do this, you will need to multiply the phase-voltage by the phase current by the power factor -for each phase.


What is the procedure to convert kilowatts?

For watts to kilowatts move the decimal place three places to the left. 500 watts = .500 kW. For kilowatts to watts move the decimal point three places to the right. 1.5 kW = 1500 watts.


If 5000 watts operates 230 volts three phase what will it draw in amps?

21.739 a 21.739 a


Why would electric cost more on a three phase system as compared to a two phase system?

Three phase electricity, per watt delivered, is cheaper than single phase. This is because you can deliver the power to an electrical appliance over three "power lines" instead of one. For example, if you tried to operate a 5 hp ac electric motor on single phase it would require 3730 watts for continuous operation and quite a bit more for start up. A 12 gauge standard wire is only rated for 2700 watts. The more current that runs thru a wire the hotter it gets. The hotter it gets the more the resistance (ohms) goes up. Resistance in a wire is pure waste in terms of electrical cost since you are paying to convert electricity to heat. The same motor run on 12 gauge 3-phase wiring would only deliver 1243 watts per electric line to run the 5 hp motor. Also for motor use, three phase is much smoother and "torquier" than single phase since the power pulses to the field magnets is matched far better than in the single phase. For a visual on this see the website description below: = Wikipedia: Three-phase electric power =


Power conversion formula for single phase to three phase conversion?

A 'watt' is the SI unit of measurement for power, whereas the 'British Thermal Unit' (BTU) is the Imperial unit of measurement for energy. Power and energy are two different quantities, so you cannot convert watts into BTUs. (Besides, who would use a BTU these days?)


How do convert Million units to megawatt?

It the unit is watts, megawatts is millions of watts, so to convert watts to megawatts, multiply the number of watts be 1,000,000.