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Our electric range is hardwired to a 40 Amp circuit with 4 copper wires (ground, black, red, and white neutral). I don't think it was ever installed correctly since each of the bare wires was just screwed into the terminal block without any terminals.

I want to do this right for our new range, so I bought some terminal lugs but I'm not sure if they are safe to use because of the current requirements.

Oven Terminal Block: Oven terminal block

Terminal Lugs: Terminal Lug

Some lugs had a max temperature warning of 90 degrees Celsius but these had no warning. Am I safe to use these? Will they be able to handle the load? Will there be any copper vs. aluminum mismatch between this and the terminal block?

I believe the main 3 wires coming out of the wall are all 8 AWG 7 strand.

Here is a link to the terminal lugs for reference: https://www.alliedelec.com/thomas-betts-btc0208/70092679/

  • Do you have a make/model # for the oven? – ThreePhaseEel Nov 3 '18 at 23:28
  • How many wires are coming out of the wall? 3 or 4? Is there a ground wire coming out of the wall, along with a separate neutral wire? – Harper Nov 3 '18 at 23:34
  • 4 wires. I disconnected the ground strap as you suggested. – eek142 Nov 4 '18 at 22:11
  • The oven is a Whirlpool WFE525S0HS – eek142 Nov 4 '18 at 22:14
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If you have 3 wires coming from the wall (hot hot neutral, no ground), then you hook the wires to the 3 terminals that you see. Note the odd little strap linking the neutral stud to the chassis of the range. It is "grounded" to neutral. Any fault with the neutral wire will energize the chassis at one of the hot voltages. Yikes.

If you have 4 wires coming from the wall (with ground), a little work is required, but this increases safety. First you remove that odd little strap, as you will be connecting neutral and ground separately. Then you attach the ground wire to that green terminal you just removed the strap from. That lug in your photo is a fine method to do that! Then you connect hot-neutral-hot to the 3 studs, much like the above.

The T&B lug connectors in your question are certainly good for 40A. UL would not let them label for #8 wire if they were not good for 40A. They are undoubtedly a good choice for ground wire. For "hot" wires, after torquing their screw to spec, I would wrap them with shrink tubing or electrical tape.

I agree with 'Bat that the T&B connectors are a little concerning as far as hitting the chassis or something else. That compartment doesn't apear to have a cover, and they seem awfully exposed. See how they fit (you are sure to be able to use one) and make a judgment call. As far as the ring terminals he is recommending, you will need larger ones that fit on #8 wire. They do make those, but not necessarily insulated. Then you can shrinkwrap them with shrink tubing. Just use black.

Uninsulated is good, though, as you can solder them with a nice large soldering iron, not the electronics pencil types but either the inductive gun type or the really big 16" long types. For the solder, go out of your way to find old fashioned lead solder (non-RoHS; RoHS compliant unleaded solder will crystallize over 10-20 years, it is a death sentence for any eelctronics built that way). Do not use plumbing solder, it's acid core and not lead.

On a 3-wire connection, the neutral is so important that I would not trust a ring crimp terminal alone. I would use one of the T&B lug connectors, it doesn't matter if that makes contact with chassis.

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    I updated my answer with a couple remarks about the crimp terminal after reading your answer. – batsplatsterson Nov 4 '18 at 12:36
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    There are 4 wires coming out of the wall. I ended up disconnecting the ground strap and using those T&B lugs. There fit great and there was no risk of them touching one another. The strain relief fitting also gave me confidence that the cables wouldn't move around much. I screwed the chassis cover back on after I was done. As long as those lugs are safe for the amperage / temperature, I think we're good. Thanks for the help! – eek142 Nov 4 '18 at 22:12
  • Also I could have avoided all this trouble if I had checked the bottom drawer of the oven... The instruction manual and terminal lugs were packed away in there. Oddly enough, they weren't copper. They looked like aluminum. Maybe they were nickel plated copper. – eek142 Nov 4 '18 at 22:14
  • @eek142 likely aluminum or zinc plated aluminum. Aluminum is a preferable choice for lug, since it plays well with both copper and alumimum wire. Copper lugs/terminations don't play nice with aluminum wire, which is why there was all the trouble in the 70s and 80s. – Harper Nov 4 '18 at 22:21
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I would not try to use those lugs, they are not really made for use with a binding post, they could handle the current, but they are just too big and clunky for that space, I could see them rotating into each other and shorting or possibly shorting to the cover.

What you want is a crimp on insulated ring terminal, similar to the ones you see on the other wires:

Burndy YAD8CM6E14

You can buy these ring terminals with a hole to match the size of the stud.

The crimp ring in the picture is uninsulated. Insulated crimp rings might be a bit safer. Their insulation is typically rated for 105°C / 221°F - probably higher than the wires you're using. I don't think you could say without consulting with the manufacturer what temperatures you might reach at the terminals. You could also tape or use shrink tubing on the terminal base but those also have temperature limits. (There are special purpose terminals, tapes, and shrink tubes that are made to withstand very high temperatures, but those are mostly used in industrial applications, not installing ovens.)

You crimp these onto the end of the wire with a tool like this Channellock 909 Crimping Pliers:

Channellock 909 Crimping Pliers

With STRANDED wire, crimp terminals (IME) make a good secure termination, but use a simple tug test and inspect your termination. There should be no movement of the wire in the terminal when crimped.

  • A lot of the crimp on connectors like the ones you posted had max operating temps of 90 degrees Celsius and looked like they were for more low voltage operations. How sure are you the terminal lugs can handle the current? The oven was supposed to come with lugs shaped like the ones I bought but there weren't any. – eek142 Nov 3 '18 at 21:55
  • the temperature rating is because of the yellow insulation .... you can get them un-insulated, or with high temperature insulation .... google uninsulated crimp connector – jsotola Nov 3 '18 at 23:00
  • edited with more details regarding crimp terminals – batsplatsterson Nov 4 '18 at 12:36

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