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Backfeeding with a portable generator - REAL safety concerns???

Generally speaking, we were using 2/0 for distribution and 4/0 for some of the transmission. 1/0 was available, but we didn't use it.

'Tips of the Trade - Grounding'

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Somewhere I've got a videotape of grounds testing.. showing what would happen when a grounds protected conductor was energized while shorted to ground. It would demonstrate what would happen with something like a 10,000 amp short for 3 cycles on the grounding cable.

Cable just jumps around a bit.

'For example, a Grade 5 clamp with AWG 4/0 cable must withstand 43,000 amperes for 15 cycles without losing its conductive protection of the worker.'

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Harry Homemaker hooks up his 5000w generator to the mains and backfeeds the entire output into the transformer. The transformer steps up the 240v to 7200v (at 100% efficiency) which puts less than 1 amp on the 7.2kv line.

I doubt the lineman even notices. If that ground clamp spits or moves, it's not installed properly.

Regards,

Jim

Reply to
Jim
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I was called to a home with an electrical emergency were a male plug was being energized. It was caused by a tenants attempt to backfeed the dryer outlet. The home had a split buss panel and the dryer breaker was on the main breaker buss.

-- Tom H

Reply to
HorneTD

Did all the magic smoke leak out of the wires?

Gunner

"At the core of liberalism is the spoiled child - miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke

Reply to
Gunner

Darwin plugs often lead to this result, almost as if Sir Charles had laid out the design in 1859.

Negroes seem to have a close affinity with Darwin, strangely enough.

--Tim May

Reply to
Tim May

Your best and safest way is to have two receptacles side by side. then you have your Grid power powering up one receptacle and your generator powering up the other receptacle. when the grid goes down, unplug from the grid receptable and plug into your generator plugin. then it don't matter if you forget anything. the only thing that can happen at this point is that you'll run out of gas/oil for your generator.

That is the cheapes safest way. AT no time should you have a double ended male cord. That is too dangerouse, specially if you have kids in the neighbourhood

Reply to
Roger

The BEST way is to use a transfer switch. The problem with the two receptacles side by side approach is that hard wired equipment - such as the control for your heating system, circulator, igniter, blower (if so equiped) - won't get power. In addition, the two receptacles side by side approach is limited. By the time pay for the wiring for enough receptacles to make practical use of even a small

5 kw generator, you'll spend more than you would if you had a transfer switch installed.

The OTHER problem with the side by side receptacles is it almost screams for a double male, which, as you said, should never be used. But when one has been without power for enough time and is cold because the thermostat won't work, guess what happens.

Reply to
ehsjr

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