My background is mechanical engineering so not great with the electrical side. I plan on buying a air-preheater (resistive wire heated) which has a power rating of 30kW, supplied by 3-phase. I need to determine whether my 3-phase supply (415V 32A) has a max current that can cope with this. My calculation is as follows:(adsbygoogle = window.adsbygoogle || []).push({});

since purely resistive, power factor =1 hence, kW=kVA=30kW

line to neutral voltage=line to line voltage/3^1/2=230V

3-phase power is 30kW, therefore single phase power = 10kW

Current=VA/line to neutral voltage=10000/230=43.478 amps

As far as I am aware this is the current rating from my supply i would need to achieve 30kW from 400V. Do my calculations appear correct? If so I will need to find a power supply rated above this current.

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# Required current rating of 3-phase power system

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