[donf]

Last night's gift!


#1 - The charred and melted insulation pad on the back of the faceplate
#2 - The charred and melted faceplate - front
#3 - The remains of the receptacle and conductors
#4 - The charred outlet box and heat streaks up the wall.

Note - This receptacle was not in use and had nothing plugged into it. This particular circuit fed all four of the bedrooms.

[parttime]

From the looks of the plugs in the first picture that baby was packing a load. Surely this is a job your on and not your place?

[donf]

Parttime;

Unfortunately this little bit of happiness came from the front bedroom in our home. Also, there has never been any thing plugged into this receptacle.

[parttime]

Wow, that's scary.

[hfcarson]

Wow...time to think about some arc fault breakers? This is the kind of thing they were intended to protect against.
Glad to see it didn't travel too far.

[donf]

I'm getting a new main panel as soon as I can scratch up the money. The current panelboard is a split bus MLO panelboard.

I'm not going to grandfather the change out. I'll go with current code and put those breakers in.

I should have done it sooner, but being on Social Security only leaves very little money. However, one serious wake up call is all that I need. My wife didn't raise a fool.

[WallyHelps]

Unfortunately this little bit of happiness came from the front bedroom in our home. Also, there has never been any thing plugged into this receptacle.

I always thought you'd need to have some current flow before the aluminum wire would cause a problem!
What is the theory as to why there would be any heat (or arcing) if no current was flowing?

I always like learning new stuff.
WallyH

[donf]

Wally,

Nice to hear from you again. Yes, you need current flow to generate heat. I can only speculate that the receptacle failed or the insulation on neutral failed because there is about two inches of bare neutral still attached to the receptacle, An arc is all that I can think of. Nothing was plugged into that receptacle.

You can see the extension cord that was run from the adjacent wall on the floor. Jim didn't want to use this receptacle because the window leaked.

[hkstroud]

Don,
You have been complaining about that aluminum wiring for years. Time to either pull it out and replace or convert all the connections with the approved copper pigtails.

Because the outlet was not being used does not mean that there was not current flowing through the circuit.

This particular circuit fed all four of the bedrooms.

Went on call about a week ago where customer had one kitchen outlet on one side of sink with transformer of cordless phone connected. Had a light fixture plugged into outlet on other side of sink. Customer said outlet with phone connected was intermittent, wouldn't keep phone charged. Also said the lamp would sometimes take about 10 seconds to come on. Of course every thing worked fine at the time and would not fail for me.

My first thoughts were that the quick connect holes were used wire the outlets and a bad connection had developed. I pulled the outlets to find that not to be the case. House was about 30 years old and customer said that no electrical work had ever been done. House was so old that it had fuses not circuit breakers. I could tell that there were other outlets on the circuit but I could not find them because there was so much junk in the house. There was a path through the dining area and living room, everything else was cluttered with junk. So much junk that if you could see an outlet, you couldn't get to it.

Evan though the outlets were working at the time I decided to replace them. I remove the fuse and replaced the outlets. After replacing the outlets neither would work. My meter showed 8 volts at each outlet. Now I am thinking faulty neutral.

Remove the panel cover and checked the neutral. All the wiring, including the hot, look good. I remove the fuse and check the incoming center terminal of the fuse holder. Had 120 volts. Put the fuse back in and check the shell of the fuse holder and had 120 volts going out. So I have 120 volts in and 120 volts out of the fuse, why do I only have 8 volts at outlet?
I touched the hot wire out of the fuse holder and about one inch of insulation crumbled. Remove the wire and the end of the wire was almost entirely burned away.
Apparently there was a loose connection that had been arcing for 30 years until it finally burned the wire into.

[WallyHelps]

This particular circuit fed all four of the bedrooms.

Ah, that makes sense now. I'm not an electrician, but if I'm understanding correctly this outlet was in the middle of the circuit and would have hot-in and hot-out connections. The load was located somewhere downstream, but if one of the connections in the burned outlet was loose, it would be in series with the load and arc.

Thanks for the education.
WallyH

P.S. Interesting story, BTW.