Braided Cloth Wire/ TCCW

[Paul Maggiore]

Inspected a home today built in 58'. The sub-panel within the home had been updated to Square-D at some point. From reading previous posts I understand the pictures I've attached likely show "tin coated copper conductors" or TCCW as it may be referred to. Appears the home is partially wired with TCCW and modern romex. The two main conductors were fed from the main distribution panel located on the exterior of the home. This main panel was a FPE stab-lok panel with a 70amp main circuit breaker. I wasn't able to remove the deadfront cover since the tab the screw engaged was snapped off. I plan to recommend further evaluation of the main stab-lok distribution panel. Also planned to recommend further evaluation on the TCCW - appears pretty deteriorated - but I wanted to bounce it off some veterans. Thanks in advance.

[Robert Meier]

Since that's a subpanel the EGC's and neutrals are required to be separate and the bonding screw needs to be removed. from the neutral bus. If all of those cables are in a single raceway you could have some derating issues as well.

[Roy D. Cooke, Sr]

Some of that is older then 1958 I am sure 1958 was all copper and Plastic bushing came along I think a little later the 58 . I started in `1951 We had 25 cycle when I started the trade and wasbeing converted to 60 cy..
Tinned copper was just about over by then .
I think it could be a time to upgrade .
Roy

[mwolff]

Originally Posted by Robert Meier

Since that's a subpanel the EGC's and neutrals are required to be separate and the bonding screw needs to be removed. from the neutral bus. If all of those cables are in a single raceway you could have some derating issues as well.

This is a 3 wire sub panel, if you remove the bonding screw, you will no longer be grounding the enclosure. So grounds and neutrals all feed back on the bare neutral. Otherwise, lets face it, you would have no ground here. TCCW would not be a concern to me unless the insulation on it was cracked, broken, charred, or no longer pliable.
To me it looks like additional circuits have been added, and possibly could overload the feeder to this panel, which in turn, may or may not trip the FPE outside. Anyway, a 4 wire new conductor to this panel would be best if it is deteriorated, then seperate grounds and neutrals, and bring wires in through there own connections. This should have been done since it is a newer panel and would require 4 wire today.

[Robert Meier]

Originally Posted by mwolff

This is a 3 wire sub panel, if you remove the bonding screw, you will no longer be grounding the enclosure. So grounds and neutrals all feed back on the bare neutral. Otherwise, lets face it, you would have no ground here. TCCW would not be a concern to me unless the insulation on it was cracked, broken, charred, or no longer pliable.
To me it looks like additional circuits have been added, and possibly could overload the feeder to this panel, which in turn, may or may not trip the FPE outside. Anyway, a 4 wire new conductor to this panel would be best if it is deteriorated, then separate grounds and neutrals, and bring wires in through there own connections. This should have been done since it is a newer panel and would require 4 wire today.

Yes, I missed the fact that this is a 3-wire feeder and left the 4-wire part out of my post. The feeder should be replaced. So some of the potential problems:
-No 4-wire feeder
-Multiple EGC's twisted together under one screw
-Derating issue with all conductors in one raceway
-Bonded neutral bus

[Paul Maggiore]

Thanks for your input guys.