Operating at unity and rated power factor

[ogbuehi]

Now I just finished reading this thread: 238-4843. If I read correctly is it to be understood that even though a generator may be rated at 1000kVA (we'll use 4160V) can not be run at 1000kW at a pf of 1? I thought that PF basically showed you how much of your current was being used for work versus overcoming reactance. I also thought that engine horsepower was based on its ability to provide the necessary amount of torque required to provide the generator's max current producing capabilities. I wasn't quite sure why it mattered to the engine's capability if the generator was providing 240Amps at 1000kW at pf 1 or 800kW at .8 pf.

 

[dpc]

Maybe a misconception has crept in. A 1000 kVA generator can almost certainly operate at 1000 kW with pf of 1 with no overloading problems. HOWEVER, this does NOT mean that the prime mover will always be rated to produce 1000 kW continuously.

A 1000 kVA generator at 0.8 pf will often be coupled to an engine rated at 800 kW.

 

[ogbuehi]

Thanks. I get it now. The current that is produced to do actual work is provided by the generator. The current to overcome reactance is done by the generator. Thanks again for the explanation.

 

[waross]

Hi ogbuehi;
You are getting it.
All the more impressive considering that you read thread238-4843.
That thread had some solid information but the good information would be hard for you to extract from the interspersed but well presented misconceptions.
One gem of misconception; "Furthermore the term 'watt' as applied' to electrical systems is meaningless."
My favorite post, that also expressed my feeling, was by our friend and MVP electricpete;
"my head hurts "
Had the thread not been closed, I would have given him a star.

Bill
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"Why not the best?"
Jimmy Carter