I have four electric cables feeding juice to my shop. There are two R 2 AWG
aluminum 600 volt cables, one slightly smaller one with a yellow stripe,
and a separate insulated copper ground. That makes FOUR separate cables
going out there, not one that has four wires in it. The outside diameter of
the R2 is 7/16"
including the black insulation. The smaller one with the yellow stripe is
3/8" diameter, and the ground is 5/16". They are 165' long.

Can anyone give me more about capacity/usable amperage with that
information?

Steve

On Dec 6, 9:27*am, "Steve B" wrote:
I have four electric cables feeding juice to my shop. *There are two R 2 AWG
aluminum 600 *volt cables, one slightly smaller one with a yellow stripe,
and a separate insulated copper ground. *That makes FOUR separate cables
going out there, not one that has four wires in it. *The outside diameter of
the R2 is 7/16"
including the black insulation. *The smaller one with the yellow stripe is
3/8" diameter, and the ground is 5/16". *They are 165' long.

Can anyone give me more about capacity/usable amperage with that
information?

Steve

Steve-

Take a look at

http://www.kellyhayes.com/catalog/WireandCable1-web.pdf
&
http://www.southwire.com/documents/C...hart_Final.pdf

my best guess is that you have
2ea 2 gage
1ea 4 gage (might be 3 gage)
1ea 6 gage

I'm thinking that someone goofed by spec'ing a small neutral but if
the loads are mostly 240v it might not be a problem.

In aluminum 2-2-2-6 is good for 90 amps with 75C insulation
4-4-4-6 is good for 65 amps with 75C
insulation

You've got what appears to be 2-2-4-6.
If the loads per leg are balanced (ie max imbalance is 65 amps) then
your good for 90 amps.
If the loads are imbalanced you'd be limited to 65 amps.

This is probably a situation that will work but isn't quite kosher.

Something tells that this is not allowed by code..... perhaps one of
our code experts will chime in.


cheers
Bob

On 12/6/2011 11:27 AM, Steve B wrote:
I have four electric cables feeding juice to my shop. There are two R 2 AWG
aluminum 600 volt cables, one slightly smaller one with a yellow stripe,
and a separate insulated copper ground. That makes FOUR separate cables
going out there, not one that has four wires in it. The outside diameter of
the R2 is 7/16"
including the black insulation. The smaller one with the yellow stripe is
3/8" diameter, and the ground is 5/16". They are 165' long.

Can anyone give me more about capacity/usable amperage with that
information?

Steve


Are there any letters on the #2 wire insulation that look like TW, THHN,
RHH, XHHW? If the wire is in free air, it will carry a lot
more current. Depending on the insulation, the amp rating could be
as high as 150 amps.

TDD