Close Call! - ECN Electrical Forums

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Pictures taken Dec 28/06

Fire department said it was water in the meter that caused this meltdown. I have my doubts.

These old style meter bases ("A"-base meter) are very common around here and are used as a disconnecting means by the power company. There are forks that slide up and the screws tend to get worn to the point where it's difficult to get them tight. This is especially true with rental homes where the power is disconnected and reconnected frequently as tenants change. My theory is that the lugs were worn and couldn't be tightened enough.

House was vacant as owner was out of town for Christmas holidays....luckily a neighbor saw the meter burning up and called it in. Another good thing is the house is clad with stucco, which probably helped prevent a fire. We will be repairing it this week as the house is for sale.

- Randy

This is a classic example of regional differences. Many people see our New England style service cable services and think it's just plain weird. When I see a service like this I think it's just plain weird. [Linked Image]

Like my first trip to visit a friend in Las Vegas, and of course what was the first thing I did? Look for the breaker panel. Little did I know that it was outside (all in one.)

Peter

Randy, is all that white in the picture snow, or just extreme glare?

Wow, close call indeed!!

Randy: Save that socket assembly if you can, I'd like to get it from you to dig into and see if the cause was as you said. PM me if you can do it. [Linked Image]

(A while ago on another thread I had mentioned that I would be interested in starting an electrical forensics service, so any good "toys" like this would be helpful.)

My own apartment has five of those bad boys..the POCO's meter reader said they plan on replaceing them this year with electronic meters, which use standard Form 2S sockets.

edited for spelling

[This message has been edited by mxslick (edited 01-02-2007).]

I'd seriously be interested in what actually caused this... I'd be more willing to bite on the loose connection theory of Randy's vs. the water idea (the water would've vaporized before the lofty temperatures this equiptment has seen) Gotta love the old school LR there too [Linked Image]

I'm 99.9% sure it was a loose connection in the forks that caused this. I've seen it before, but not to this extent.

If you look at the hole in the bottom box (closeup picture) you can see what's left of the two line lugs. Usually the POCO uses the left side lugs for line, then it goes up the stabs and through the meter, and back down the other stabs to the load lugs.

Once we get into this job in a couple of days I'll know more of what actually happened. I've also got old parts for these meters, so I'll include some pictures of what it should look like.

CT, that is snow you see. [Linked Image]

I go to a lot of fire investigations and I don't hear too many correct answers coming from fire fighters. Water might have caused enough corrosion on the terminals to cause a connection to fail. The damage is an arcing fault caused by insulation failure which may have been caused by water or heat from a poor connection.

I hope you'll post an "after" picture when you get the replacement service completed.

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Here's the finished product. The PoCo hasn't connected yet, so there's a cover over the new meter socket. It was definitely caused by loose connection on the line side of the old meter and there wasn't anything that could be salvaged because it fell apart as we were removing it. The black on the wall was from the plastic blocks that burnt. These hold the meter, wire connections and sliding meter stabs in place.

-Randy (Sixer)

Randy, is all that white in the picture snow, or just extreme glare?

Molten or burnt aluminum. Most of these terminal boxes that I have seen are cast aluminum.

[This message has been edited by yaktx (edited 01-08-2007).]

Note also that in place of an A-base meter, there is one of those plastic socket-base adapters.

Yaktx, I assumed the white he was talking about was on the steps, but you're right,
the old A-base meter was cast aluminum and the burnt parts were white. I also should have mentioned the socket adaptor. Thanks.