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enter image description hereenter image description hereI have placed two induction surface units on top of our 30-year-old GE coil element stove (model JSP31GOP1WH). I have removed all four coil burners. Each of the induction units is rated at 1800 W at 120 V so each draws 15 A. The instructions for each unit states to plug into a 20 A circuit, but we have only one 20 A circuit available. Right now we have both connected to that circuit through a 20 A GFCI duplex receptacle. We only turn on one unit at a time.

Obviously I could install another 120 V 20 circuit, but I would like to get power through the heavy 4-wire aluminum cable (original 53 year-old 50 A GE breaker) that the stove appliance cord connects to through a NEMA 14-50 receptacle behind the stove.

My first thought is to connect a 12 or 10 AWG cable (3 + gnd) to the connection block on the back of the stove where the cord connects. I would route this behind the stove to a box surface mounted on the top back of the stove (magnetic hold fast?) or just resting there. This would be a multiwire branch circuit sharing a neutral or two separate neutrals wired to a 20 A duplex receptacle.

Another thought is to snake the 12 AWG cable through the back of the stove into the 3 inch high space under the stove top but I have pretty much rejected that.

The oven of the this stove still works and we are reluctant to buy a new induction range if this cheaper solution would work.

EDIT

The suggestion in one answer or comments is to install a subpanel to obtain both 240 V and 120 V power from a 6-6-6-6 aluminum cable fed by a 50 A breaker in the main panel currently going to a NEMA 14-50R.

The purpose of this would be to get two 120 V 20 A circuits to operate the two countertop induction cooktops sitting on top of our 30-year-old GE electric range. I have removed all four coil elements to prevent damage if a coil were accidently turned on. Currently both induction cooktops (each rated at 1800 W so 15 A at 120 V are plugged into one dedicated 20 A circuit. I cannot use both at high power. One unit is a 2-burner and one is a 1-burner but each is rated at 1800 W total. The 2-burner will allow all 1800 W on one burner, but will divide power if both burners are on to keep the total power at 1800 W or less.

I want to keep the 240 V power to the NEMA 14-50R because the GE range is plugged into that and the oven of the GE range is working perfectly. It is not a forced air oven, but an old fashioned "still" oven, but we find it OK. I have a sentimental attachment to this oven because a now deceased friend was instrumental in getting the faulty oven timer/control unit repaired since a new one was not available.

I would install the subpanel in the wall of the room the kitchen stove backs on and would put a picture over the subpanel. I want to bring existing 6-6-6-6 aluminum cable into the subpanel and take 6-6-6-6 copper from the subpanel into the box for the NEMA 14-50R so I can use the highly rated Bryant NEMA 14-50R which requires copper conductor.

The subpanel would have two 20 A 1-pole breakers for two separate 120 V circuits for the two separate induction cooktops. Should the subpanel also have a 2-pole breaker (40 A minimum per intructions for GE range) for the 6-6-6-6 copper to the 14-50R or can I just connect through lugs?

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    The inside of the stove with the still-working oven is not a suitable place for any wiring other than high-temperature appliance wiring, and even if you used that, would constitute a modification that would void the stove's UL listing.
    – Ecnerwal
    Commented Jun 28, 2023 at 22:49
  • All the wiring under the stove top is high temp insulated but it does not get very hot just from the oven. The oven is well insulated. I turned on the oven and this space did not get hot at all. It is the electric resistance surface units that really heat up that space and these as I said have been removed. However, I did not run a self cleaning cycle to see how hot it became during that. We have run a self cleaning cycle maybe 5 times in 30 years. Commented Jun 28, 2023 at 23:44
  • Could I use a 20 A inline fuse in each hot to protect from overcurrent? Or is there setup with overcurrent breakers that would fit in a box with the duplex receptacle? I am just wondering what could make this work and be safe at the lowest cost. I would not do anything that would void the insurance. Commented Jun 28, 2023 at 23:48
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    Are you sure the range feeder is 4-wire? (A ground wire can be retrofit). Commented Jun 29, 2023 at 0:10
  • Wait, don't kitchens have two 20A receptacle circuits? Commented Jun 29, 2023 at 0:21

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Might as well stop paying for your insurance coverage, they will laugh all the way to the bank when that turns up if you need to make a claim.

You potentially COULD do this in a legit fashion by installing a 50A sub-panel, if you can provide working space for a sub-panel.

Connecting 15A devices or 12 AWG wires to a 50A breaker without a sub-panel and 15 or 20A breakers FIRST - no way. Having watched my oven element turn to incandescent slag while the stove's breaker went "ho, hum, not more than 50A" I can affirm that it would be a rather severe fire hazard.

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  • In the UK low current demand devices are plugged into high current capacity ring circuits protected by very large breakers.. They protect the low power device by having a fuse in the plug. Are there any 120 V plugs in the US with a 20 A fuse or overcurrent breaker in the plug? Similar to gfci plugs in hairdryers. Commented Jun 29, 2023 at 1:38
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    Doesn't matter if there are. If YOU are not in the UK, having a receptacle those hypothetical plugs could plug into connected to a 50A breaker is a violation in the US. And Canada, as far as I know.
    – Ecnerwal
    Commented Jun 29, 2023 at 1:44
  • Could I put in a subpanel that would be in the wall behind the stove. I would not be able to access the panel without pulling out the range. Thealternative would be a subpanel opening on the other side of the wall in the next room. I am beginning to see that I am just going to have to put in another 20 A 120 V circuit. Commented Jun 29, 2023 at 2:09
  • What about 12 or 10 AWG 3+gnd cable from the connection block to an industrial 2-pole miniCB in a special box with 35 mm DIN rail? From there to a box with a duplex receptacle. Commented Jun 29, 2023 at 7:32
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    You're still talking about attaching undersized wire to 50A circuit. And you still need working space for the sub-panel. The other side of the wall could work if you can keep the working space of the panel clear. But running new wire is probably going to be simpler, yes.
    – Ecnerwal
    Commented Jun 29, 2023 at 12:01
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Since the range is scrap anyway, I would hack the range.

They make dialects of Eaton, Square D and Siemens breakers that have mounting screws on their face and are meant for face-of-enclosure installation. Modify the range so instead of the four heat level knobs, those are now breakers. One 15-20A 2-pole breaker for the oven, and then 2-3 more 20A breakers feeding 2-3 120v receptacles mounted on the back of the range. Notice how common 120V receptacles are designed for face mounting on equipment simply by drilling and nibbling two oval holes and three screw holes; or alternately nibbling a big rectangular opening for Decora and two screw holes.

Rockwool insulation and plenty of it to keep the oven's heat away from the equipment. Use high-temp wire (finding that would be the trick; try GALCO, Grainger or McMaster-Carr). Then do something cosmetic to blank over the entire cooktop. Alternately, you could get induction units intended for installation into a surface and install them.

Make sure you have an honest 4-wire connection because running a contraption like this 3-wire would be a recipe for fatality.

This advice is 100% NEC legal (can't say the same for UL) because NEC doesn't regulate appliances; UL does. UL would probably treat it as "A PDU/power strip with a built-in oven" for White Book compliance.

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Funny thing is that I'd had a similar scenario with my piece of rusted junk GE drop in stovetop. I, too, had fathomed that since to wall oven and stovetop shared the same power source (a 6 awg cable from a 60 amp breaker) that an electrician junctioned off threaded 10 awg line to power the four stove coil elements that used threaded 14 awg lines to each element, i thought i could used that fat gnarly junction cable to pigtail 10-2 solids to a 220 outlet. Something (specifically the guy at my local ACE hardware store) told me to STOP and consult an electrician. In response to, "Who?" he wrote down the number of the best in the area (who's currently wiring two mansions and a marina but mercifully stopped by to consult me (and gander at why so many homes around here burn. Answer: uncertified do-it-alls bungle electrical work for shameless sums whilst tapping your liquor cabinet dry). He advised a dedicated 20-amp breaker for each of the two 1800 watt induction cooker on its own circuit, though I may opt for a 20 amp double pole breakers to serve the 220 outlet or pigtail link two outlets on the same circuit using 12-2 line. I think that'll work. I plan to add a 2-eye LPG fueled cooktop that needs only enough electricity for spark ignition. Bottom line is that we both seem to see the value of flexible, non-fixed, pluggable countertop cooking options that in the long run are more cost efficient and easily upgradable one unit at a time. Cheers.

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  • Ho, is this actually answering the question? Commented Dec 8, 2023 at 5:40
  • I take this "answer" to be an admonition to STOP trying to figure out a way to use the original 50 A 4-wire circuit #6 aluminum cable to power two 1800 W 120 V induction surface units, and a 240 V oven. In fact I have already done so because I realized that I simply couldn't risk the consequences of non-standard wiring. I have taken one of the 1800 W induction units out of service and moved the other to the counter, I replaced the resistance coils back in the stove. My wife and I both have major health challenges and I don't want to set up any arrangement even remotely possibly unsafe. Commented Dec 8, 2023 at 12:06
  • Some formatting and a read through how to write a good answer would help a lot in helping others make sense of your answer. Editing out some of the fluff like your plans for an LPG cooktop (which is irrelevant to the solution), would also help.
    – FreeMan
    Commented Dec 8, 2023 at 15:40
  • Thank you for the critique. As for relevance, I expressed appreciation for the poster who also is opting for not-fixed appliances, and another who also has opted for a smaller, portable, easy to fill propane tanks. It's relevant because it all ties together with efficient, proper electrical circuits and more efficient kitchen appliances. I've also disconnected the huge bottle of liquified cash and connected a 100-lb propane tank that i fill for $20 at the local country store. I'm also correcting the wiring thanks to all of you whose expertise is vastly greater than my capabilities. Thank you. Commented Dec 12, 2023 at 21:22

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