Fire

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A branch fell off a tree and pulled the 2" riser over and away from the house. The fire department pulled the meter but the triplex was still hot. A few hour's later there was a electrical fire in the kitchen. The owner also said before the fire his dog touched the ground wire going to a phone line down low and it shocked the dog. What could have caused the fire?
 
Ronnie Barham said:
What could have caused the fire?
Energized neutral/EGC or water piping is my first guess.

A couple of years ago, a customer had an electrical fire. The #10 EGC supplying the water heater burned its entire length. A 200 amp service upgrade had been done some time back, but had all the signs of no permit or inspection: No cable clamps, no grounding at all, etc.

The service cable to the meter was still the old copper #4 SE, but the cable leaving the panel was 4-0 al. No other grounding had been done. The water heater's piping was the only intact "electrode", and the #10 EGC was the only GEC. The drop fell due to a branch in a storm.

Oh, and even after the fire dept. had the POCO pull the meter, there was still power in the house. There was voltage to earth on the drop's neutral, so I was told. Sound familiar?
 
Someone fell asleep with a cigarette? Or the candles being used for light caught something? Or the gas stove being used for heat and started something else on fire?

What are the odds that a house that had the power disconnected had a fire that was started by the electrical? The odds are pretty much against it.

What are the odds that a house without power would have a fire started by a cigarette, a candle, or someone trying to make some substitute for all the things they are missing with the power? Very high.

How do you know the fire was electrical?
 
I saw a fire that started almost exactly this way. A car hit the power pole and broke the service mast as well as the one of the ungrounded conductors and the grounded conductor of the service drop. The remaining ungrounded service conductor was shorted to the mast and meter can. This energized everything that was connected the the electrical grounding system. The building was a duplex with a common steel gas pipe between the two units. The current ran on the EGC to the furnace and then on the flexible gas line to the metal gas pipe and to the other unit where the gas pipe had some path back to the utility grounded conductor. The current burnt a hole in the flex gas line and started the escaping gas on fire. The homeowner put the gas fire out with his extinguisher and called the fire department.
 
don_resqcapt19 said:
I saw a fire that started almost exactly this way. A car hit the power pole and broke the service mast as well as the one of the ungrounded conductors and the grounded conductor of the service drop. The remaining ungrounded service conductor was shorted to the mast and meter can. This energized everything that was connected the the electrical grounding system. The building was a duplex with a common steel gas pipe between the two units. The current ran on the EGC to the furnace and then on the flexible gas line to the metal gas pipe and to the other unit where the gas pipe had some path back to the utility grounded conductor. The current burnt a hole in the flex gas line and started the escaping gas on fire. The homeowner put the gas fire out with his extinguisher and called the fire department.

I don't doubt that that happens once in a while, but that still sounds like a zebra to me. For a house that has the meter pulled, if I heard hoofbeats I would think of non-electrical caused first.
 
steve66 said:
I don't doubt that that happens once in a while, but that still sounds like a zebra to me. For a house that has the meter pulled, if I heard hoofbeats I would think of non-electrical caused first.
Steve,
If the meter was just pulled and there was no damage to the service riser or other line side service equipment, I would never consider looking for an electrical cause for a fire in that building, but with damage to the service and reports of shocks, I would take a close look even where the meter has been pulled.
 
How long was it before the fire dept pulled the meter????? I would assume that there was a neutral loss for a period of time - which started some appliance or device in the kitchen smoldering - then the meter gets pulled - a while later that smoldering that started eariler ignites - fire.... Far fetched - but from my experiance - it could happen....

Or - the use of gasoline and a match to collect insurance money is involved.

Dog getting shocked by phone line - I have an interesting story - which many have probably heard from many sources many ways.....

For entertainment value - here's mine:
I was working in phone terminal room in a building, and the phone guy walks in, we start talking and eventually get around to talking about wacky service calls we've been on. (This part is fact - the rest - I don't know) So he starts telling about this one - He goes to a service call where the owner claims that her phone has not rung in 10 years. He gets there and asks the woman why after ten years of her phone not ringing that she is only now calling to report it. She then tells him that she had a dog that would bark wildly whenever someone was calling - which she tought was neat that he somehow knew that people were calling - so she never reported it, and would even have people call and check as a novelty. People would call - the dog would bark - she would pick up the phone and people were there.... So he asks, "So where is this dog?" And she gets a little upset, the dog died a few days before, and she still wasn't over it, and she loved him so much.....

So the phone guy gets to work, and eventually traces the problem to a termination can up on a pole in the womans back-yard. There was a short to grounding terminal in the can from the tip side of the pair going to her house. He thought that odd because this short would not allow the phone to work at all - That ground must have some sort of problem - so he started to trace that.... A little further down the pole he noticed a worn spot on the ground conductor - it was worn all the way through.... 'Well thats wierd' he thought. He re-ran the ground fixed the short in the can and called the customer on his butt-set from the pole - the customer answered, and says, "Great - you fixed it! What was wrong?" And comes to the window where she can see him still up on the pole. So he tells her, "Well there was this short up here on the pole, but what was odd is that your phone shouldn't have worked at all, and there was the open ground wire down below.... Was there something around the pole before???" - She says, "Yes there was - my dogs runner was up there and ran all the way to the house." - The phone guy thinks to himself for a moment and says happily, "Oh, thats why your dog would bark - everytime the phone would ring he would get shocked in the neck - man that must of hurt... Ten years of getting zapped in the neck - WOW!"

He sees his customer burst into tears, and drop the phone..... Packs up leaves....

FYI a ringing phone is roughly 90v 20Hz - and hurts like 277 IMO.....
 
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