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I have had my kitchen remodeled. I have new cabinets and a stone countertop. When it came to hooking up the oven, I was told I needed a neutral wire for the oven to work after the cabinets and countertop had been installed. My house was built in 1953, so there was no original neutral installed. The cabinet is on island. How can I make the oven usable without destroying the new cabinet and countertop. If a transformer is used will that solve the problem? I live in the United States.

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    Neutral been used forever, ground is the iffy one. Imagine your stove uses 240v but you only have two hots and a ground. If you have the old cable in place, only need a new cable with neutral and/or ground to replace it, no destroying needed.
    – crip659
    Feb 9, 2023 at 1:08
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    @Ruskes How do you know that? The working assumption (me, Harper, crip659, possibly some others) is that the original cable is actually two hot and neutral. That is an important distinction because: 1 - a legitimate bare neutral can be converted to ground, but a real ground can't be converted to neutral and 2 - ground can be retrofitted (as explained by Harper) but neutral can't. Feb 9, 2023 at 4:14
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    @Ruskes We don't know for sure if OP is mistaken or not. It is quite common for wiring that old to have a bare neutral, which is commonly mistaken for a bare ground. It is also possible, but generally with much more recent installations, to have an oven that doesn't actually need a neutral so that none was actually installed. We don't know. Pictures will tell us what is actually going on. Much as in many other questions vague references to a type of product leave unknowns but specific model #s allow for definitive answers. Feb 9, 2023 at 4:28
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    @Ruskes There are certain very specific cable types which have a bare neutral (Harper discusses this). Those cable types may be identifiable in a picture. Feb 9, 2023 at 5:20
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    Are you sure it's not possible to run new wiring without destroying the new kitchen cabinets and countertop? It might be possible.
    – user253751
    Feb 9, 2023 at 8:57

1 Answer 1

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Where the existing wire is "/2+ground" (black white bare) cable, It was never legal to wire a 240V range or oven which needs neutral. But many bad installers did it. Ranges have no need for 120V except for the oven light. At the time, the concept was "every house has a bunch of 120V incandescent bulbs fit for oven lights". Today, that concept is dead.

Where legacy /2+ground exists, the only option is to replace the cable run, or obtain a range/oven that does not require neutral.

With SEU or "/3 no ground" there are options.

Option 1: NEC 110.3(B) Follow Instructions.

Oven circuits included:

  • 2 hots and a neutral up until 1966
  • Either way until 1996
  • 2 hots, neutral and ground after 1996

Most likely, you are looking at SEU* type cable, which is 2 insulated hot wires and a bare neutral. Really. I can understand confusing it for ground, but it's neutral. *It can be used as a ground but doesn't have to be.

Now, NEC 110.3(B) requires you install equipment according to labeling and instructions (implying: "Read them"). Those instructions may tell you how to connect your range to a 3-wire "hot-hot-neutral" connection. If so, you can simply do that.

However, be warned: 3-wire connections have a serious problem, and that's why they were outlawed in 1996. They've killed a lot of kids. When the neutral wire loses connection (a routine failure), it energizes the chassis of the range. I'm absolutely not a fan.


* "Service Entrance, Un-armored" is designed for the first bit of wiring between the weatherhead and the main breaker. This comes from the power company and does not have a ground. Ground is established at the main breaker, via ground rods.

Option 2: Install a GFCI breaker and don't connect ground

The standard instructions tell you on 3-wire connections to wire the oven chassis to neutral. I hate that. Instead, you can install a GFCI breaker at the panel, and then, follow the 4-wire connection instructions, which tell you do not wire the oven chassis to neutral. In this configuration you connect ground to nothing. (that's important for the GFCI to protect you).

Now, if the neutral wire gets loose, nothing happens except the oven light stops working. If a hot wire contacts chassis, the chassis becomes energized and that's fine - because as soon as someone touches it and starts to be shocked, the GFCI instantly trips.

Do not connect oven ground to neutral in this instance.

If the range connects via socket and plug, use 4-prong socket and plug and label it "GFCI Protected / No Equipment Ground". These labels come with every GFCI. Wire the stove according to the instructions for a 4-prong plug (separate neutral from ground).

Option 3: Retrofit ground.

With great care to keep neutral and ground separate, a #10 ground wire can be retrofit via any achievable route from the range (4-prong socket if used) to any of the following:

  • The panel, obviously
  • Any place with a #10 ground going back to the panel (e.g. water heater or A/C)
  • Any place with non-flex metal conduit back to the panel
  • the bare copper Grounding Electrode System wires from panel to ground rods or water pipe.
  • Do not ground to gas or plumbing pipes.

Now you have 4 wires honestly, and use a 4-wire grounded connection in the normal way.

Option 4: Hack the range to not use neutral

Generally, the loads on a range that care about 120V are quite small. They could be supplied by a transformer of practical size. Any UR-Recognized transformer with 240V and a center tap should suffice. It can have a secondary that just wouldn't be used. Of course that would violate NEC 110.2 and 110.3(B), however not that much if your manufacturer makes a version of this range for the Philippines. That's exactly what they do with those ranges, except they wire it for a 240V oven light.

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  • Apologies for sliding into this question, but can I ask a point of clarification? If a manufacturer's spec says, "3 wire, 240v" (Wolf induction cooktop, it happens), do they mean black-white-bare, or black-white-red-bare? Feb 9, 2023 at 1:57
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    @AloysiusDefenestrate You can't be sure, best to check the instructions. They often say "240V" as slang when they mean 120/240V. But if "240V" is truthful, then yes, black, white taped black, ground - and notably, obsolete SEU cable (black-black-bare mesh) can be re-tasked for that. Feb 9, 2023 at 2:22
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    @AloysiusDefenestrate I double-checked - the instructions really are not clear. But I think they mean "3 wires as opposed to 4 wires", so hot/hot/ground. In which case that could be: black/white/bare cable (a.k.a. /2 cable with ground), black/red/white/bare (but not using the white=neutral, a.k.a., /3 cable with ground), or black/red/bare-or-green-or-metal-conduit - a.k.a., wires in conduit. It is only "black and white" if it is a /2 cable - anything else and it is "black and something else" (usually, but not always, black + red or two blacks). Feb 9, 2023 at 2:23
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    Well, a cooktop probably doesn't need neutral. Generally it's ovens as they want to support 120V oven lights for some reason that made sense in 1992. Feb 9, 2023 at 2:38
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    @AloysiusDefenestrate ask a new question!
    – FreeMan
    Feb 9, 2023 at 14:28

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