Cloth covered Single Conductors

[guitarman21632]

I am trying to determine what the actual type of wire is that was installed circa 1950-60's. The conductors have a cloth covering over a rubber insulation and was used in conduit like THHN. I have always referred to it as cloth covered THHN but I know that is not correct. Anyone have any idea? I am thinking it might be Type RH but I need verification to help resolve an issue on a project I am currently working on where this wire is installed.

 

[ActionDave]

I don't even know what that cloth covered insulation is called. The only time I have ever seen it is in old BX, I have never seen it pulled in conduit.

 

[infinity]

Likely RW, RH or RHW.

 

[Tony S]

In the UK it’s VIR (Vulcanised India Rubber). Now well passed it’s sell by date.

 

[GerryB]

Likely RW, RH or RHW.

I know it is a problem for solar supply side taps. The Ilsco insulating piercing bugs that are popular for that are not rated for cloth covered wire.

 

[guitarman21632]

My assumption was that it was Type RH and, after talking to a couple inspectors that have been around the block a time or two, they confirmed my suspicions. It is Type RH which is a fire-retardant cable and you can only use the 60 degree column for rating.

 

[hbiss]

Likely RW, RH or RHW.

Yup. Used it back when I was half way around my first block.:lol:

-Hal

 

[fandi]

Hello,
I have a similar question:
It's a 1940-50 building in Southern California. The cloth wires feed a lighting fixture. Despite no new work involves, as soon as such cloth wires are found, they have to immediately replaced, yes? (No grand fathered in because there is fire hazard in my opinion). Do you know a NEC code section that prohibits the uses of existing cloth wiring? Thanks a lot.

 

[infinity]

Hello,
I have a similar question:
It's a 1940-50 building in Southern California. The cloth wires feed a lighting fixture. Despite no new work involves, as soon as such cloth wires are found, they have to immediately replaced, yes? (No grand fathered in because there is fire hazard in my opinion). Do you know a NEC code section that prohibits the uses of existing cloth wiring? Thanks a lot.

The NEC does not prohibit the continued use of rubber insulated conductors. Even knob and tube is still permitted.

 

[norcal]

The only problem is a lot of lighting fixture manufacturers require using 90C conductors. But it's only been about 30 years that 90C conductors have been required w/ NM sheathed cables & THHN conductors being the more common conductor used in conduit.