## Terminology (power)

Hello all. I recently read something that has me a bit confused. Consider a single-phase 100kVA transformer that supplies a 40kW heating load at unity power factor. What is meant by "how much additional kW of inductive load at 0.8 power factor can the transformer carry" mean? Is it asking how much more real power will the supply be transferring to the load given it is no longer unity?
Seems odd talking about a transformer "carrying" kiloWatts.
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 Mentor 40 kW at 1 PF is 40 kVA. 100-40 is 60. So how many kW is 60 kVA at .8 PF? Yes, that's real power.
 (60 kVA)0.8=48 W. Essentially they are simply wanting to know how much more real power the source can supply to a load with 0.8 PF given it is still supplying the unity PF heating load?

## Terminology (power)

So yeah, 48KW of true power will give you an apparent power of 60KVA at a PF of 0.8.
 Yeah, this is exactly why I asked. I felt as though it was worded awkwardly; in a way that none of my textbooks have ever worded a problem. I see where you are coming from, though. I drew a phasor diagram, ended up with two triangles, then applied Sine Law and ultimately ended up with the same result as you! Regards!
 Recognitions: Gold Member Science Advisor Thanks Sandy - diverse methods came to same number, so i am convinced it's right. But what a wakeup it was for me to see how easily i leapt to wrong answer ! my self discipline needed a tuneup.. I wonder if that was a subtle choice of words, or did author make same mistake? thanks old jim