Aluminum Wire Termination

Let me give you some background on aluminum terminations. Aluminum conductors in the past were made with AA13000 series alloy. This particular alloy was rather unstable and created problems with terminations. With the AA 13000 alloy, it was necessary to take steps to combat problems caused by cold flow, heat expansion and oxidation.

For several code cycles now the NEC has specified AA8000 aluminum compound for conductors. This compound is quite stable and does not experience the problems of the older compound.

Aluminum terminations are evaluated by UL and the evaluations are done without the use of oxide inhibitor. UL in their “White” book (General Information for Electrical Equipment), 2002 edition has the following information: Page 133, Wire Connectors and Soldering Lugs (ZMVV) it states: “Conductor Termination Compound-Some connectors are shipped pre-filled with conductor termination compound (antioxidant compound). For non-prefilled connectors, conductor termination compound may be used if recommended by the connector manufacturer as preliminary preparation of the conductor. Wire brushing of the conductor may also be performed if recommended”.

All building wire is required to be manufactured with the AA8000 series alloy. However, some single use USE and some overhead type conductors may be manufactured with other alloys. This is the reason that you will see connectors used for overhead conductors sometimes pre-filled with oxide inhibitor.

In most cases it is not necessary to use oxide inhibitor on aluminum terminations, unless the manufacturer specifically requires this in his instructions. These instructions will accompany the product.

I realize that this is not exactly the information you were requesting. However, I do hope I have been of some assistance. If you desire more information please do not hesitate to contact me.

You can contact me at (307) 638-0307. You can contact UL at (800) 595-9844.

Mike Forister, NEMA

March 11, 2003

Copyright © 2002 Mike Holt Enterprises,Inc.
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