Does the insulation on old SER cables ever fail?

jamiedolan · 02-28-2009, 11:54 AM

I am curious if this "insulation" looks like waxed paper on the old SER cables ever fails. If it did, in my main panel, I would clearly have a direct short. After seeing first hand what the results are of a direct short on unfused service, I want to avoid one.

Does the insulation on old SER cables ever fail?-img_5409.jpg

Does the insulation on old SER cables ever fail?-img_5411.jpg

Once I do my service upgrade, this will of corse be gone. I just started thinking, what if one day, my load is a bit on the high side, these conductors get just a little warm and that insulation goes...

Jamie

junkcollector · 02-28-2009, 07:50 PM

I have a hard time believing that it is just the paper wrapping insulating the bare conductors. I would say that you probably have rubber insulation under the wrapping. Cable insulation like that and any other cable insulation is going to be compromised when excessive current flows, but your main breaker "should" trip before you overheat your service conductors.

joed · 02-28-2009, 10:57 PM

Looks like electrical tape recolouring a conductor to me.

Plumber101 · 02-28-2009, 11:54 PM

Looks like to me that the wire are either neutral or grounds in an older load center possible XO box. The white tape on the black is more likely ID for neutral

jamiedolan · 03-01-2009, 12:03 AM

Quote:

Originally Posted by Plumber101

Looks like to me that the wire are either neutral or grounds in an older load center possible XO box. The white tape on the black is more likely ID for neutral

The cables in question are the large 2awg black and red wires one shown in each photo. The is AL service cable from the meter to this panel. The white that is taped is a piece of thhn feeding my sub panel I installed.
Jamie