Really REALLY brittle SE cable.

[220/221]

We have all run across very brittle old wire before but it is usually only on the exposed ends. I changed a resi panel today and found some really bad stuff going to the range, cooktop and oven. I chopped out some of the wall to get into what should have been fresh cable but the wires were just as bad there.

Any bending and the insulation just cracked off. I stripped about a foot of sheath and put a couple wraps of tape to try and keep the insulation in place and tried to avoid bending them at all.

Anaconda, 6/3 circa 1960. I would HATE to find this being used as unfused service conductor inside someones home. The entire lenghth would have cracked off if it was manipulated at all.

The sheath said 6/3 but it doesn't look like 6 to me.

 

[George Stolz]

Was it overloaded?

 

[Paul B]

I would say it was an 8 and overheated for sure.

 

[iaov]

It looks like it has been hot.

 

[peter d]

Not surprising..it's been cooking in Arizona summers for the past 40 something years.

 

[Pierre C Belarge]

Based on your post, the integrity of the conductor insulation is degraded. There is no choice but to abandon the cable and install new. I would not reattach it, and let the customer know. It is very importan to properly explain this to the customer so the can understand the situation as best as is possible.

 

[macmikeman]

I have seen the after affects of se cable from the service connections to the meter when this type of insulation has degraded to that point. KABLOOEY!!
My old boss from way back who had just about every type of license and a degree in chemical engineering once told me that that type of cable sometimes develops a hydrogen gas when it degrades like that, further increasing the chance of enery release during a short circuit.

 

[Cow]

I know replacing cable through someones finished house sucks for them. But, you gotta draw the line somewhere. That stuff is so burnt, I would of not hooked it back up. Not even temporarily.

You can replace a lot of cable for the price of one burned down house. And nothing is worth the price of somebody possibly getting killed.

I wouldn't leave something like that in my house......

 

[wawireguy]

Don't touch it, lick it, mess with it... Unless you are replacing it. If you don't screw with it, probably ok.

 

[Pierre C Belarge]

Don't touch it, lick it, mess with it... Unless you are replacing it. If you don't screw with it, probably ok.

Have you ever meggered a conductor with insulation in this condition??
The conductor shown in the picture and his explanation show that this is not okay.

 

[220/221]

Thanks for the replies. I will have a talk with the HO today and explain my concerns. I KNOW I will have a fight on my hands.

 

[weressl]

Some thoughts that may well serve to understand the possible contributors to the failure and to remember:

The introduction of synthetic insulation material has been fraught with problems. We thought that XLPE was the most marvelous insulation material for MV cable insulation - and certainly cheaper than EPR - before it was discovered that it was highly susceptible to treeing after a few years in service. Products that are made by chemical reactions exhibit various stability over time. In other words they degrade with time. One of the methods to test materials is in a heat chamber where the material is exposed to higher than normal temperatures to simulate the aging process and they extrapolate the results. Some of the early tests were less than reliable in predicting the true age. The completeness of the reaction, the purity of the compounding of the materials and the quantities to assure completed reactions that leaves no un-reacted component behind all contribute to the longevity of the materials, all else being the same.

One shining example is some of the Chinese Christmas lights that you can see deterioration after trying to string them after a few years of use.

 

[zappy]

We have all run across very brittle old wire before but it is usually only on the exposed ends. I changed a resi panel today and found some really bad stuff going to the range, cooktop and oven. I chopped out some of the wall to get into what should have been fresh cable but the wires were just as bad there.

Any bending and the insulation just cracked off. I stripped about a foot of sheath and put a couple wraps of tape to try and keep the insulation in place and tried to avoid bending them at all.

Anaconda, 6/3 circa 1960. I would HATE to find this being used as unfused service conductor inside someones home. The entire lenghth would have cracked off if it was manipulated at all.

The sheath said 6/3 but it doesn't look like 6 to me.

The copper looks smaller but the insulation looks thicker.