Current Calculation

If I have a 3 phase 300kW load (purely resistive) and is fed from a 3 phase 415V supply, how do i calculate the current flow considering the network is fed from 3 x diesel generators which are providing a supply with a power factor in the region of 0.8.  As it is a heater (purely resistive load) do I use unity power factor or pf of 0.8 to calculate the current flow? 

Power Systems
Electrical Engineering

asked 1/19/2015

2 Answers

This answer has been selected by the question author as the best answer.

Use unity power factor.  The 0.8 is a generator factor between maximum kW and kVA which can be produced.  If you search myElectrical, there is a post explaining where this comes from. 

answered 1/20/2015 Steven McFadyen 246
Steven McFadyen
  • The note explaining generator operation limits is here: - Steven McFadyen 1/20/2015

Thank you very much Steven, much appreciated.

answered 1/20/2015 Johnjkjs 6

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