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Donnie Raines
02-16-2005, 11:28 AM
Do to a very interesting claim I am involved in at the present time, I have a rather odd question to ask(don't worry...I have no autority over the settlement of the claim...I am just the agent.... :cool: ). Is it possible for a circuit breaker to trip if the electric running to the house has been turned off?...if something was to have shorted, the wire gets hot etc etc....

Bob Hovde
02-16-2005, 11:37 AM
If the electricity has been turned off, there's no way for the wire to get hot.

Bob

Donnie Raines
02-16-2005, 11:40 AM
If the electricity has been turned off, there's no way for the wire to get hot.

Bob


You and I are on the same page.... ;)

David Wilson
02-16-2005, 11:42 AM
Donnie
If there was a thunder storm in the area it is possible. The only other way it could happen is if a generator was being used.

Bob Hovde
02-16-2005, 11:55 AM
Donnie
If there was a thunder storm in the area it is possible. The only other way it could happen is if a generator was being used.

You're right about the lightning. I fried a TV once in Ohio. It took out the power supply and "crystalized(?)" the wires. I replaced the power supply board, but then gave the TV away because the picture wasn't good anymore. The new owner replaced all of the wires and the picture came back.

Lightning does strange things. :eek:

Bob

Ken Fitzgerald
02-16-2005, 11:55 AM
If all normal power is secured to the house, then there is no power to trip the breaker. If, as David stated, a generator was being used for power the house or lightning were to strike between the "shutoff" and the house or if it stuck nearby, the resultant power could run in on the power lines and trip the breaker. Unless a breaker malfunctions, for a breaker to trip, there must be power applied to it.

Jeff Sudmeier
02-16-2005, 11:57 AM
Yeah, this shouldn't be able to happen. Unless power is applied to the end of the line. We have tripped breakers before when the whole sub panel breaker was off, but we accidentally applied power to the end of one of the runs under the sub. Anyway, it is highly unlikely.

Michael Perata
02-16-2005, 12:58 PM
Sorry to be the obverse one here.

Most circuit breakers are mechanical devices and they wear out. If a breaker had been tripped in the past, it may not reset completely, and even with the power off, mechanically, not electrically, trip itself.

Steve Jenkins
02-16-2005, 1:37 PM
If there is no power to the house how would you know and what difference would it make.

Donnie Raines
02-16-2005, 1:45 PM
If there is no power to the house how would you know and what difference would it make.

The electric company can confirm if service was canceled. It is a big deal in confriming the source of the loss.

Rob Russell
02-16-2005, 5:50 PM
Donnie,

It sounds like there was a fire and "wiring" is being blamed as the cause of the fire.

If there was no electric company power to the building, it's pretty tough to have current to overheat a wire.

One way that I could think of this happening is if you backfed a panel from a generator and the circuit breaker had become defective so that it wouldn't trip on overload. Imagine hooking up a 4000 watt generator to a standard receptacle. If you had a bad breaker that didn't trip, you could conceivably feed 30+ amps through that 15 or 20 amp circuit and that could be enough current to overheat some connections and start a fire.

Rob

Steve Nelson
02-17-2005, 1:04 PM
Sorry to be the obverse one here.

Most circuit breakers are mechanical devices and they wear out. If a breaker had been tripped in the past, it may not reset completely, and even with the power off, mechanically, not electrically, trip itself.
the breaker may not set after tripping many times but it will not trip mechanically

Michael Perata
02-17-2005, 1:22 PM
Steve

I can recall on at least two occassion where I had installed CBs in a new panel in a new house and BEFORE power was dropped to the house, breakers failed to keep a mechanical set. (Recollection is the CBs were Sylvania)

Admittedly this situation is different from Donnie's problem, but I have had CBs fail mechanically.

Steve Nelson
02-17-2005, 1:41 PM
Michael, thats what I was talking about,if you look at a tripped breaker it is in the half way position and a mechanical failure the breaker is in the off position

Donnie Raines
02-17-2005, 4:01 PM
Sorry I am so vague in my question here. Do to the nature of the situation, I don't want to give to much away until it has been settled...at which time I will enlighten all of you to this situation. It is rather unique to say the least.

Chris Padilla
02-17-2005, 4:53 PM
CBs are thermal devices. When they heat up (i.e. from current flow) to a certain point, they will trip...mechanically. Upon tripping, they cool down relatively quickly.

Look forward to "...the rest of the story..." , Donnie! :)

Randy Moore
02-17-2005, 6:43 PM
Donnie,Like everyone else I am interested in the rest of the story. It will be interesting to hear the story behind your question.

Randy