Replies

1. 
   Guest_ | Feb 25, 2000 12:39am | #1

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   My picture of what you're doing is using some type of butt splice where the Al and Cu conductors will be spliced end-to-end and not laying alongside each other. This seems ok to me, assuming you're using properly sized connectors.

   You might want to check the NEC Art.210-19(c)Exc.1 to make sure you've got the taps right.

   Also (since you asked about any possible code violations) Art.338-4 (on SE installation) refers you to Art.336 (on NM installation). Section 336-26 lists the ampacity for romex (and SE) as that of 60-degree conductors. From Table 310-16 you can see that the ampacity of #6 Al at 60 degrees is 40a, not 50. Thus your breaker should really be a 2-pole 40.

   Have fun ..........Lee

2. 
   tomm_ | Feb 28, 2000 11:02pm | #2

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   Ed Lee,

   Thanks for the input. I checked all your NEC references in the only code I have, 1996. Section 336-26 was'nt there, but Table 310-16 was. As I interpret it, SEC cable is rated at 75-degree C and as such is spec'd to 50A. (NMC like romex is 60-degree.) Does 1999 code change that?

   Thanks for the help.

   Tom

3. 
   Guest_ | Feb 29, 2000 12:34am | #3

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   Double check w/ an electrician. My understanding was there is only one approved splice for copper to aluminium. I believe it's called copalum and the splices need to be mechanically crimped with a hand tool made by the same company specifically for those fittings. From what I gathered, you had to be trained to use the tool before you could get the double secret code to buy the stuff you need.Then again, my dad was a signalman for the railroad, and they handle the splices the same way you did! Jeff

1. 
   Guest_ | Feb 29, 2000 03:45am | #4

   *I checked my '96 book, and yes it is different. The reference is in Art.336-30(b). However, this is in Part C of Article 336, so the reference from Article 338 on SE cable, which mentions only Parts A & B, didn't apply. Weird huh. I guess you're probably grandfathered in, so I stand corrected. As for the mention of AMP connecter, that is a different situation used generally to make splices in smaller branch-circuit conductors like #12 and #14 gauges. This is used to correct problems with the aluminum romex used for a while in the 60's. For larger conductors, we make splices frequently between copper and aluminum, using a variety of connectors that basically keep a conductive but not reactive alloy between the copper and aluminum surfaces. It sounds to me that that is the type you are using.Thank you for your investigative response! Lee

1. 
   Guest_ | Feb 29, 2000 06:33am | #6

   *Ed Lee, that's exactly the situation (60's 12/14 gauge aluminium) that I was investigating when I crossed that info. Thanks for clarifing it for me. I was about to start working in a condo and every other one had Alum. wiring. After learning that I didn't want to get into it by myself, I checked my clients wiring ready to call my electrician, and discovered out of the 10 units in her building, she was the only one to have all copper! Must have been the last unit wired, and after they switched from alum! Jeff

4. 
   tomm_ | Feb 29, 2000 06:33am | #5

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   I recently helped a friend wire his new oven and cooktop. The 50A supply to the old range's junction box had aluminum 6 gauge SEC. Our solution to wire the new oven and cooktop to this was to use Cu/AL rated "splices" (metal tube with large compression screws)and pig-tail 6 inch, 6 guage copper plus ground and insulate with heat-shrink. Luckily the cooktop and oven were 240V-only units (no neutral - just black, red and green) so we just used wire nuts to make the connections. Since the outer conductor of the SEC cable is now used only as a ground (no current), it seems that this should be safe and comply with the latest code.

   Does anyone see a safety issue or code violation? Any help would be appreciated.