What Temperature Wire is This??

[Joethemechanic]

Old, no markings, not sure what to call it. Cloth maybe? Think it's asbestos?

Also what gauge would you guess it is? My caliper said 0.68 inch is the OD of the conductor plus the insulation. I'm thinking 3/0.

 

[ramsy]

I would follow raceway to termination points, and check wire there.

 

[Deltaforce]

I would follow raceway to termination points, and check wire there.

Look like junk yard matreial to do that!

 

[infinity]

Looks like tin coated copper condcutors with RHW insulation. Table 5 in Chapter 9 lists #3/0 RHW with a diameter of .630". #4/0 RHW is .688"

 

[Joethemechanic]

I would follow raceway to termination points, and check wire there.

To do that I either have to pull the meter, or work hot and un-tape split bolts

 

[Joethemechanic]

Looks like tin coated copper condcutors with RHW insulation. Table 5 in Chapter 9 lists #3/0 RHW with a diameter of .630". #4/0 RHW is .688"

So do you think 75C temp rating should be used? Three phase with a reduced size neutral in 2 inch rigid

 

[ramsy]

Looks like tin coated copper condcutors with RHW insulation. Table 5 in Chapter 9 lists #3/0 RHW with a diameter of .630". #4/0 RHW is .688"

Pg.1 of Table 5 in Chapter 9 lists #2/0 RH?? with a diameter of 0.668"

You quoted Pg.2, which designates (*) as special note
*Types RHH, RHW, and RHW-2 without outer covering.

 

[ramsy]

So do you think 75C temp rating should be used? Three phase with a reduced size neutral in 2 inch rigid

Get correct conductor size first, before exceeding 60C temperatures

 

[Joethemechanic]

Get correct conductor size first, before exceeding 60C temperatures

Yeah I guess I'm going to have to pull the meter to find out.

I know it's from 1953 and they loaded it hard. Running 2 and sometimes 3 welders, a 15 HP air compressor, machine tools, eighteen 1500 watt block heaters for the trucks, and about 8,000sq ft of shop + 900 sq ft of office.

I'm never going to load it like that, but it would be nice to know what it can handle

It's a 240/120 open delta high leg BTW

 

[ramsy]

If disconnected, and Megger tested, that 82 year-old service wire is likely in need of replacement.

 

[Joethemechanic]

If disconnected, and Megger tested, that 82 year-old service wire is likely in need of replacement.

Yeah well if I pull the meter I'm defiantly going to test it with my megger. But it's still surprisingly soft and flexible and shows no signs whatsoever of being overheated. I don't know how that is possible considering the machinery that was in here, and I know they were hard facing buckets for the mining shovels. Almost all the wire in here is nice and soft like new almost all of it in ridged