Mark C. Posted September 20 Report Share Posted September 20 The ground is aluminum for sure but yes the new wires should be copper including the ground. Msheffield 1 Quote Link to comment Share on other sites More sharing options...
neilestrick Posted September 21 Report Share Posted September 21 2 hours ago, Msheffield said: Also, my dad just noted that the wire is actually aluminum but connected to copper fittings, and he was thinking maybe that was a bad combo? I have no idea. But when I get the new wires, should I get copper? Yes, you need copper. Aluminum is not recommended for kiln circuits. Msheffield 1 Quote Link to comment Share on other sites More sharing options...
Bill Kielb Posted September 21 Report Share Posted September 21 (edited) 10 hours ago, Msheffield said: the wire is actually aluminum but connected to copper fitting Yes best case aluminum to copper terminations require regular maintenance and often compound (anti oxidant paste) along with maintenance to ensure the connections remain safe, tight and well connected. If you use compound, they are made specifically for the metal in the wire and termination. Codes usually dictate this specifically. Aluminum wire must also be derated so in the table below #6 wire copper = 55 amps @ 60c terminal rating and #6 Aluminum is derated to carry ONLY 40 amps @ 60c terminal rating. Aluminum and kilns, strongly discouraged. Edited September 21 by Bill Kielb Quote Link to comment Share on other sites More sharing options...
Msheffield Posted Monday at 01:21 AM Author Report Share Posted Monday at 01:21 AM On 9/20/2024 at 5:25 PM, Bill Kielb said: Yes best case aluminum to copper terminations require regular maintenance and often compound (anti oxidant paste) along with maintenance to ensure the connections remain safe, tight and well connected. If you use compound, they are made specifically for the metal in the wire and termination. Codes usually dictate this specifically. Aluminum wire must also be derated so in the table below #6 wire copper = 55 amps @ 60c terminal rating and #6 Aluminum is derated to carry ONLY 40 amps @ 60c terminal rating. Aluminum and kilns, strongly discouraged. Very interesting, and good to know. Do you think this might have also led to accelerated corrosion in my brass element connectors? Several times in the past two years I've had to take everything apart and sand it down, because they corrode so quickly. Might also just be climate, but I noticed the same black residue on them as in the outlet. Quote Link to comment Share on other sites More sharing options...
Mark C. Posted Monday at 02:05 AM Report Share Posted Monday at 02:05 AM YES-aluminum needs specail coatings like no nox to prevent corrosion at terminaltion points-look it up. I suggest copper for all kiln use. Feeder wires etc Quote Link to comment Share on other sites More sharing options...
Bill Kielb Posted Monday at 02:14 AM Report Share Posted Monday at 02:14 AM (edited) 53 minutes ago, Msheffield said: Do you think this might have also led to accelerated corrosion in my brass element For aluminum to copper or brass it is mostly just a function of the aluminum. Your element connections are brass copper and nichrome (or similar) so a good variety of properties all smashed together. Environment is a significant factor (high humidity. It may sound silly but larger connections with more mass and area to air cool generally perform better than smaller lighter connections with a smaller heatsink capacity. So temperature is a significant accelerant as well. Often connections in kilns are not cooled well so maybe the top hottest connection corrodes first because of the updraft cooling. So my observance, environment #1 (hard to control) and keeping the connections as cool as possible definitely helps. Edited Monday at 02:16 AM by Bill Kielb Quote Link to comment Share on other sites More sharing options...
Msheffield Posted Monday at 02:44 AM Author Report Share Posted Monday at 02:44 AM 38 minutes ago, Mark C. said: YES-aluminum needs specail coatings like no nox to prevent corrosion at terminaltion points-look it up. I suggest copper for all kiln use. Feeder wires etc Well, when I re-wire, I will definitely be using all copper then! Quote Link to comment Share on other sites More sharing options...
Msheffield Posted Monday at 02:45 AM Author Report Share Posted Monday at 02:45 AM 30 minutes ago, Bill Kielb said: For aluminum to copper or brass it is mostly just a function of the aluminum. Your element connections are brass copper and nichrome (or similar) so a good variety of properties all smashed together. Environment is a significant factor (high humidity. It may sound silly but larger connections with more mass and area to air cool generally perform better than smaller lighter connections with a smaller heatsink capacity. So temperature is a significant accelerant as well. Often connections in kilns are not cooled well so maybe the top hottest connection corrodes first because of the updraft cooling. So my observance, environment #1 (hard to control) and keeping the connections as cool as possible definitely helps. Hm... would it be worth running a little fan under the wiring box to help it cool faster after firing? Quote Link to comment Share on other sites More sharing options...
Bill Kielb Posted Monday at 03:15 AM Report Share Posted Monday at 03:15 AM (edited) 1 hour ago, Msheffield said: Hm... would it be worth running a little fan under the wiring box to help it cool faster after firing? It usually helps with the temperature aspect a bunch. When we have failing main bus equipment often a fan extends the life temporarily until new busses can be fabricated, scheduled and installed. For kilns, leaving the element tale a bit longer to be more in an airstream, or some splices are just larger and a better heatsink and can be a passive solution for those one or two that fail prematurely. The cooling needs to take place during the firing though, not so much after. Edited Monday at 04:14 AM by Bill Kielb Quote Link to comment Share on other sites More sharing options...
Msheffield Posted Monday at 05:01 AM Author Report Share Posted Monday at 05:01 AM 1 hour ago, Bill Kielb said: It usually helps with the temperature aspect a buch. When we have failing main bus equipment often a fan extends the life temporarily until new busses can be fabricated, scheduled and installed. For kilns, leaving the element tale a bit longer to be more in an airstream, or some splices are just larger and a better heatsink and can be a passive solution for those one or two that fail prematurely. The cooling needs to take place during the firing though, not so much after. Oh... and I had to cut my tails shorter than I would have liked, so that probably didn't help. I'll look into the fan idea. Thank you for the info Quote Link to comment Share on other sites More sharing options...
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