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wins turbine - transformer

wins turbine - transformer

wins turbine - transformer

(OP)
Hi all,
This is my first post.
I have a 480v/285a induction machine. I have a 400a breaker for it. I have a 300kva 480/208 xfmer downstream. According to the NEC I need overcurrent protection for the primary. Doing the numbers I come up with a 500a breaker.
Does this seem right? It seems to code, but it just doesn't seem right?
Can anyone help?
Also, does anyone know where I can find some good info on integrating wind turbines into diesel systems?
Thanks very much!

RE: wins turbine - transformer

Look up NEC 450. There is a range of primary breakers sizes that can be used based on whether or not secondary protection is provided and how.

Can't help on integrating WTG to diesel systems without further insight of what you have. You would need a stiff source that holds its own voltage and frequency even if the WTG overspeeds, for example, or loses the power all of a sudden. Probably not a good idea.

Rafiq Bulsara
http://www.srengineersct.com

RE: wins turbine - transformer

I assume that this is a 3 phase installation. You may use a breaker rated at 125% for the full load primary amperage.
I get 361 amps x 1.25 = 452 amps. Next size is 500 amps.
Why do you think it "just does not seem right" ?

RE: wins turbine - transformer

That is the maximum size. If your source is rated at 285 amps, the 400 Amp breaker may suffice.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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