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#21768 - 02/10/03 07:16 AM Help Need To Identify Old Wiring
Joe Tedesco Offline

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA

Please help to identify the terminology for this very old wiring. It is a single conductor in a tube like conduit that is wrapped in what I believe is a copper jacket.
Joe Tedesco, NEC Consultant

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#21769 - 02/10/03 01:30 PM Re: Help Need To Identify Old Wiring
Scott35 Offline

Broom Pusher and

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA

Looks like an older variation of GTO cabling, or maybe something for Medium Voltage equipment.
Could also be a high temperature equipment lead.

? - Does the insulated conductor have an Asbestos (or Glass Fiber) sheath on top of the insulation, or is that just the simple cloth type - akin to K&T conductors?
Also, what type of insulation? (i.e.: Thermoplastic, rubber, etc.).

I'll run though the EE manuals and see what comes up.

Scott35 S.E.T.
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#21770 - 02/10/03 02:00 PM Re: Help Need To Identify Old Wiring
ElectricAL Offline

Registered: 10/10/01
Posts: 615
Loc: Minneapolis, MN USA

This one caught my eye over at Mike's. I contacted the original poster, and this is his description:
The conductors vary in size. There are a ton of branch circuits. I haven't measured yet, but I'd guess most of the branch circuits to be 14 gauge. There are larger conductors also.

The original installation included a larger conductor feeding from a distribution point out to a wooden splice box. the box had an asbestos backing in it. The conduits were all drilled through the back. The larger conductors were apparently daisychained to the smaller conductors that in return branched out to devices.

At a later date, somebody came back and installed fuse or circuit breaker panels adjacent to the various locations of the wooden boxes.

The raceway is constructed of a black cardboard like material on the inside and a very thin copper colored tin on the outside. Additionally, a seperate raceway is installed for each conductor.

The conductors are insulated with a woven material. Oh, and yea, you are correct, the inner insulation is rubber that crumbles to the touch....
A photo of the asbestos backed wood box showed screw holes and wire positioning that, to my eye, looked correct for this to have been a panelboard comprised of porcelain fuse blocks tapped off the larger conductors used as the bus.
Al Hildenbrand

#21771 - 02/10/03 04:05 PM Re: Help Need To Identify Old Wiring
Bjarney Offline

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Type MI cable has white "chalky" fill in a copper jacket with bare conductors, so it probably isn't that.

#21772 - 02/10/03 04:46 PM Re: Help Need To Identify Old Wiring
frenchelectrican Offline


Registered: 02/06/03
Posts: 938
Loc: Wi/ Paris France { France for ...
bonsoir joe:

if that wire on outer jacket is fexibale or semi rigid like pvc thinwall plastic pipe if not it is classiffed as med voltage line to motour or transfomer it have hot conducter in the middle then the copper jacket for ground conducter i cant remember the fancy word for that one but i did seeit few place have that before i belive it called constred nueural jacket cable ( i may be wrong on this one )

merci marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)


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