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Ken Amelin
08-02-2012, 04:43 AM
This is a 60's house and the service wire is typical for houses this age.

What is the material of this wire? It looks like steel cable or is this clad copper?

Also, What is the expected life span of the wire (or sheathing)? Should we be recommending that a service wire of this type be changed due to age?

Thanx

Markus Keller
08-02-2012, 07:12 AM
The wire itself is probably aluminum, don't know if they used steel. Jerry or HG would know better than I.
However, in my experience the insulation is the big problem. As long as you don't touch it, look at it too long or talk bad about it in its presence the insulation tends to remain intact.
Look at it too long, touch it and it seems to flake off happily. The pic looks like it might be that slightly plastic'y type. That stuff isn't any better, falls of in chunks.
Looking at the wire thats in the panel and the wire as it goes into the weather head are the key exposure areas. I tell clients to have anyone be very careful about disturbing the wires. i.e. don't have your buddy install some romex line and jostle those wires. I also tell them to consider replacement sooner rather than later.
Recommending replacement isn't the worst scenario since there's usually other issues of age, deterioration or non-compliance that need to be addressed anyway.

Garry Blankenship
08-02-2012, 09:19 AM
That is rough lookin stuff. Probably tinned copper. With no exposure to the elements it should last lots longer than any of us. Not sure when the code requirement came to be, but that main C/B is not legal - - - required to be bolted, ( secured ), to the can.

Ken Amelin
08-02-2012, 09:32 AM
Here's a larger picture of the wire.
It sure doesn't look like aluminum.
The main breaker is not labeled Al/Cu.
Type MP-T - not sure what that means

Speedy Petey
08-02-2012, 02:21 PM
Not sure when the code requirement came to be, but that main C/B is not legal - - - required to be bolted, ( secured ), to the can.It is legal. There is a hold down, it's just hard to see. That white thing to the right of the breaker.

Speedy Petey
08-02-2012, 02:23 PM
That's just some really old tinned copper SEU type, service entrance cable. It's most likely near or at the end of it's useful lifespan since it has rubber based insulation which dries out.
This. +1


I see a dreaded "double tap" above the main breaker. I hope you called the local police to report this. :D

Jerry Peck
08-02-2012, 03:08 PM
Looks like tinned copper in rubber insulation, but that would be unusual in a 1960s house ... in a 1930s, 40s, maybe even 50s, yes.

By the 1950s thermoplastic insulation had come in, by the 1960s I would have thought that rubber insulation was gone and thermoplastic would have replaced all it. Possibly the thermoplastic was on the smaller size conductors - I'm trying to remember what I worked with in the mid-1960s with the larger sizes, as I recall, the smaller sizes were all thermoplastic insulated.

H.G. Watson, Sr.
08-02-2012, 05:57 PM
Here's a larger picture of the wire.
It sure doesn't look like aluminum.
The main breaker is not labeled Al/Cu.
Type MP-T - not sure what that means
Murray Breaker, 2p 100A 40C, obsolete.

Garry Blankenship
08-02-2012, 08:21 PM
It is legal. There is a hold down, it's just hard to see. That white thing to the right of the breaker.

Thanks Pete. Looks like some kind of milky white nylon sumthin-r-other.

John Kogel
08-02-2012, 08:51 PM
Looks like tinned copper in rubber insulation, but that would be unusual in a 1960s house ... in a 1930s, 40s, maybe even 50s, yes.

I agree with all, it looks like tinned copper with rubber insulation. Maybe an old timer was using up the last of his old stock?

What about that bare neutral? Now that looks like Aluminum. Would they sometimes tin the bare stranded cable? I need to go look at some other pics.

Re: really old SEC's, I will generally take a look at the wiring at the drip loop, and include a pic of that. It will be the worst for wear at the loop.