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Current Calculation Question

Current Calculation Question

Current Calculation Question

(OP)

Should be simple but I am not thinking quite right this morning.

If I am given a load and being told it requires 500kW how do I calulate the current it will draw? The load is for a large machine and will be mainly motor loads.

Would I take the 500kw divide it by the voltage * 1.73 * PF

Or do I ignore power factor and just take the 500kw and divide it by the voltage * 1.73

Thanks
Hank

RE: Current Calculation Question

With the PF and the voltage is line to line. Do not forget to multiply kW by 1000 to get W  (or use voltage in kV).

I presume this is a 3 phase calculation.

Rafiq Bulsara
http://www.srengineersct.com

RE: Current Calculation Question

You can't ignore PF because it is active power. Motor rated power is mechanical (shaft power) by default and that means you have to assume some efficiency as well: I=mech.power/(eff*sqrt(3)*line voltage*pf).
If your data assumes electrical power, then: I=el.power/(sqrt(3)*line voltage*pf)  

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