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Mark Rand Mark Rand is offline
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Default "Synch"ing with a bulb...was Electrical (gen-set) question

On Tue, 18 Sep 2007 12:59:35 -0700, jk wrote:

Jim Stewart wrote:

I can't think of a worse situation than strapping
together the two busbars of generators exactly
180 out of phase. You'd be producing a fault
current twice that of a hard short circuit. If
everything were sized for that, it's no surprise
something exploded.



I can, and thats closing in one generator to a stiff system, 180 out.
You still produce a fault 2x that of the 3phse bolted fault, but that
starts out as a larger number in the stiff system case.
jk


It would depend on the sub-synchronous reactance of the alternator, not the
synchronous reactance. The fault current would be no larger than that which
occurred with a pole-slip and a normal generator will survive that. The
operators, might need to do some laundry before appearing in public, but the
alternator should suffer no major damage.


Mark Rand
RTFM