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3 wire v 4 wire range ?
2

3 wire v 4 wire range ?

3 wire v 4 wire range ?

(OP)
Our old stove died, and when the new one got delivered the guy couldn't hook it up because it has the wrong receptacle in the wall (apparently one meant for a dryer). The required receptacle is a 3 wire (3 flat prongs), and the one I bought clearly states it is not for use on grounded circuits.

The wire in the wall is a 4 wire (2 hot, neutral, and ground). The old receptacle was also a 3 wire and the previous guy has installed both the neutral and ground on the neutral terminal of the receptacle. This seems wrong to me, but I thought I would ask here. I was thinking that I am supposed to hook the neutral and hot wires to the new receptacle, and leave the ground unattached. Is this right or wrong? What should I do?

Thanks

RE: 3 wire v 4 wire range ?

Hmmm... You got a new range with a 3-pole plug? That's odd. New ranges should have 4-wire plugs. Do you mind telling us the make and model?

Anyways, if you do have a 3-wire range, you are correct. Hot, hot, neutral -- with the neutral to the vertical lug at the bottom of the Y. The center conductor (neutral) carries some current due to 120V controls in the range. You never want to allow current to flow in the ground wires.

Quick tip: The grounded conductor (neutral) does carry current in normal operation. The ground conductor does not carry current in normal operation, but only when a ground fault exists.

Here's a pic: http://appliantology.org/gallery/image/622-wiring-...

Best to you,

Goober Dave

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RE: 3 wire v 4 wire range ?

(OP)
Thanks Dave. It is an LG we got from Home Depot. HD delivered and provided the cord so I assume it is what the manufacturer wants. The back of the unit has diagrams for both a 3 and 4 wire set up.

While I have never been able to wrap my head around how AC works (DC is easy) I knew enough that it seemed strange to hook the neutral and ground together. Thanks again.

RE: 3 wire v 4 wire range ?

Great, dcarr. In a new house, that 4-wire setup would be required. In that case, the ground (4th pin) grounds the metal chassis of the range to prevent shock. Your LG may be double-insulated, or else they wouldn't allow 3-wire hookup.

I wouldn't worry about safety, LG makes good stuff.

Best to you,

Goober Dave

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RE: 3 wire v 4 wire range ?

Strange, because most ranges and dryers, at least until a few years ago, did not include a cord for the very reason that different houses built at different times had different plugs.

The new standard, I believe, requires 4 wires. Older standards required 3, and were mixed in the 30 amp level. However some ranges were 50 amp, so required a different plug.
Now it's just so mixed up, not many of us know.

Even in a 3 wire dryer circuit, there is current in the neutral, because the motor was often a 120 V motor (and the controls).

I never could understand how a 3 wire range, had a 3 wire outlet on it's face, and still be equivlent to normal 3 wire outlet. Come to find out it wasen't the same.

The biggest difference many times is the ground is connected to the body of the device (range or dryer), and the ground jumper was removed from the neutral terminal.

In the outlet, some older houses did not have a ground run to the outlet, so you can't truly install a 4 wire outlet.

RE: 3 wire v 4 wire range ?

"HD delivered and provided the cord..."
So they simply provided the wrong cord. Return the cord and get the right one. Stoves and dryers come without cords because the manufacturer has no way of knowing in advance if the appliance is going into a newly wired home or not. Stick with four wire for the added safety.

RE: 3 wire v 4 wire range ?

While 4 wire is required by newer codes, this is a safety issue, and you should use the 4 wire system whether it is required or not.
if you've got 4 wires in the wall, use them - for safety sake!

RE: 3 wire v 4 wire range ?

I concur with stevenal.

RE: 3 wire v 4 wire range ?

And 1capybara!

RE: 3 wire v 4 wire range ?

Guys and Gals,
The 3-wire range thing went out with the inception of the 1996 NEC. That was when the change was made to only allow the 4-wire range cord. I dare say that this is a "newer" code at this point. Hello????!!! It is 2014 now!

Agree with the last 2 posts. If you don't have a 4-wire feeder, install one. Get a 4-wire cord with plug. Separate your ground and neutral. Stay safe. Happy cooking!

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