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Sym interrupting vs. Adj Sym interrupting

Sym interrupting vs. Adj Sym interrupting

Sym interrupting vs. Adj Sym interrupting

(OP)
Guys,
ETAP SC report has Symm KA rms and Adj. Sym KA rms and it uses M.F which,

Adj. Sym KA rms = M.F. x (Sym KA rms)

I am wondering how ETAP calculates M.F. ?

An investment in knowledge pays the best interest (Benjamin Franklin).
www.kookypedia.com

RE: Sym interrupting vs. Adj Sym interrupting

Out of the relevant IEEE breaker rating standards?

RE: Sym interrupting vs. Adj Sym interrupting

(OP)
I don't change any setting in the breakers and it is strange that some breakers have M.F>1 (like CB6 and CB7) and some have M.F.=1 (like CB11 and CB9)

An investment in knowledge pays the best interest (Benjamin Franklin).
www.kookypedia.com

RE: Sym interrupting vs. Adj Sym interrupting

It has to do with the types of breakers, the ratings of the breakers, and the actual system power conditions. Note that the two that are getting adjusted were tested at a more favorable power factor than the rest; they're seeing an X/R that's too high while that same X/R is fine for the breakers with the lower test PF. Try the IEEE Blue Book; the Red Book may also have some information.

RE: Sym interrupting vs. Adj Sym interrupting

See if the graphic and formulas below could help



RE: Sym interrupting vs. Adj Sym interrupting

(OP)
cuky2000,
Thanks a lot for your awesome comment.

An investment in knowledge pays the best interest (Benjamin Franklin).
www.kookypedia.com

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