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jim rozen
 
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Default Generators and Back-up power

In article , Leo
Lichtman says...

Bob wrote:
BUT, it seems to me that as a _load_ the power-less mains coming into your
house look like a dead short! I.e., the combined loads of all your
neighbors as well as the load back through your local pole pig. In which
case your generator breaker would blow in about a millisecond. (clip)
^^^^^^^^^^^^
I have always thought that too. If your genset breaker did not pop, the
motor would stall. Trying to feed voltage into a "dead short" cannot
succeed even for a millisecond. The current would try to go up, but would
exceed the breaker limit while the voltage across the line was still only a
volt or so (maybe).


Consider the case where the genset in question is out on the end
of a long, single line, where the house in question has it's
own pole pig.

And consider that maybe, the long line going to the pole pig
opened up someplace, and a crew were going to work on it.
Even if there were other houses, the load on them might not
be that extreme. Maybe they have transfer switches, so their
major loads are disconnected...

Jim

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