This could have been much worse. The pictures above show what happened inside my electrical service meter box on the side of my house on Friday (1/16/09). My 200 amp service panel is just on the other side of the wall, about two foot of 2/0 wire between here and the breakers.
Gloria told me while I was at work that the power in the house was acting “funny” and that the house was getting cold. Yes it does get cold in Texas, so we do need heat. My house is 100% electric so it meant the heat pump wasn’t working. However the emergency heat should work if it was just the outdoor unit not running. I said I would check when I get home.
When I got home I discovered the house was 62 degrees and main heat pump breaker was off in the electrical panel. When I reset the breaker it immediately snapped off again, hmm… not good. I detected a familiar burn smell. If you are an electrician you immediately know the smell I mention.
I removed the panel cover and nothing burning there. I tested with my meter and discovered one phase of the power was out. The burn smell had to be in the meter case outside the house about a foot beyond the electrical breaker box. I also realized that if I left the double breakers on and any of those loads (like the heat pumps) came on, it would cross feed to the dead side of the panel. I snapped all the double pole breakers off.
The utility company came out that night about an hour after I called them. They pulled the cover on the meter box outside and showed me what you see here. Bad news was it was on MY side of the meter. This morning I had the electrician out and was able to grab these pictures. That melted wire was about 1/64 of an inch from going to direct ground where it feeds through the case. The aluminum lug had melted and broke the circuit at the meter base just before the impending electrical explosion to ground. Look at the picture of the bushing ring and realize (grounded) steel pipe threads were inside those plastic threads shown!
I discovered after the electrician made the repair that the heat pump breaker would still not reset. We examined the wiring all the way to the heat pump compressor and there was no burn, but a check with my meter proved the compressor suffered a non repairable direct internal short. It was the only 240 volt appliance that was operating when the meter box caught fire except for perhaps the water heater. The upstairs heat pump we shut off because the upstairs is always warmed by the downstairs unit.
There would be high current (the same current that caused the visiable fire damage) through compressor windings from the compressor trying to run on the low voltage condition caused by the electrical fire in the meter panel, overheating the motor windings, shorting them out and blowing the breaker. The compressor failure and breaker trip may have saved me from a house fire. The breaker tripping removed the heavy load that was feeding the electrical fire. A few more seconds and the main feed would have gone to ground (see picture of the insulating bushing) and probably blown the meter box off the side of the house. (No fuses between there and the power company HV transformer.)
That heat pump unit had just been serviced less than two months ago and was working perfectly up until the wiring burnout. It gave up its life to save the house!
All told the damages are in the $6,000 range.
WOW Dad… that is unbelievable… ~Shel
Looks nasty, no? Yes! Come on insurance, do your thing!
Dan,
Wow … that was very close.
It looks like from the photos that the wire is 1/0 Aluminum … ??
We have a 100 service but all copper. But what cause the failure … loose connection creating the overheat condition?
And what about the other wiring? Safe?
Totally unacceptable wiring in my opinion …
Good luck,
Pat H
Pat H
Hi Pat,
Yeah, real…
The utility drop is 1/0 aluminum. The entrance is 2/0 copper and all house wiring is copper. It is the copper entrance that came loose and burned. It melted the steel/aluminum pressure clamp. Go figure the mix of metals in the clamp. However the aluminum drop cable is very typical practice and because it is aluminum is the reason it is a larger size than the copper cable.
There is probably a very large primary fuse/switch on the transformer which is in my front yard. All the wiring is underground and I have never seen the inside of my transformer box (it also serves all the houses around me), so that is an educated guess. In my business I have been around when main fuses blow and it makes the heart start pumping a lot harder! I think the meter would have blown off before the fuse opened.