Originally Posted By: pdacey This post was automatically imported from our archived forum.
If it’s bare aluminum wire lets hope it’s only used for a ground.
I see it used as a ground all the time, usually running between the Service Panel and the Sub panel. Connecting the ground bus from the sub panel to the bus in the Service panel.
Just be patient, Joe, Bob, Mike, Ryan and a few others will eventually come into this thread and we'll all know everything there is to know about un-insulated aluminum wire. 
Originally Posted By: jpeck This post was automatically imported from our archived forum.
250.62 Grounding Electrode Conductor Material.
The grounding electrode conductor shall be of copper, aluminum, or copper-clad aluminum. The material selected shall be resistant to any corrosive condition existing at the installation or shall be suitably protected against corrosion. The conductor shall be solid or stranded, insulated, covered, or bare.
Grounding electrode conductors shall be installed as specified in 250.64(A) through (F).
(A) Aluminum or Copper-Clad Aluminum Conductors. Bare aluminum or copper-clad aluminum grounding conductors shall not be used where in direct contact with masonry or the earth or where subject to corrosive conditions. Where used outside, aluminum or copper-clad aluminum grounding conductors shall not be terminated within 450 mm (18 in.) of the earth.
Originally Posted By: dbozek This post was automatically imported from our archived forum.
Jane…Jerry about summed it up and thanx for that Jerry. Aluminum can be used as a grounding conductor as long as it is properly sized as well. Copper can handle more than aluminum so one has to be careful here. Also as Jerry’s response mentioned, all aluminum wires have to be protected from corrosion. There are anti-oxidant substances out there specifically designed to do just that. Just a suggestion for HI’s…if there is no visible anti-oxidant on an aluminum connection, it should be noted. The absence of such can cause problems down the road. If anything, please refer that it be checked by a qualified electrician.
– You cannot help men permanently by doing for them what they should and could do for themselves. Abraham Lincoln
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Dan,
That was a "Yes" and a "No", depending on what, where, and how.
I thought that part of the code was pretty much self-explanatory (unlike many sections), so I did not add to it.
However, here it is:
250.64 Grounding Electrode Conductor Installation.
Grounding electrode conductors shall be installed as specified in 250.64(A) through (F).
WHAT - (A) Aluminum or Copper-Clad Aluminum Conductors.
WHERE - Bare aluminum or copper-clad aluminum grounding conductors shall not be used where in direct contact with masonry or the earth or where subject to corrosive conditions.
HOW - Where used outside, aluminum or copper-clad aluminum grounding conductors shall not be terminated within 450 mm (18 in.) of the earth.
