Electricians: Range wiring and breaker sizing code

[dstig1]

The NEC gives a mulligan to 15 and 20 amp circuits. There's so many of them out there, for the most part they work OK, it would cost a fortune to require that every device plugged into an outlet be capable of 20 amps.

Think about it: the logical thing would be to say, yes, every device on the circuit has to be capable of handling the current of the circuit breaker. For a dedicated circuit that's not unreasonable. For general purpose circuits it would mean that everything would have to be 12ga wire, because 15 and 20 amps use the same outlets. More practical just to wave the magic wand and say that low-amperage circuits aren't a problem.

Yes, I think you hit the code logic hit on the head. For general use circuits, everything that gets plugged in is much lower draw and often has tiny wires. 18 ga is not code for any house wiring, but is fine for a lamp, for example. But when it is dedicated, then you must match as there is an assumption that the appliance needs the full rating, and so the whole circuit should be rated the same. Still not sure about plugging in a 50A stove on a 60A circuit, but I guess the code logic says that is not kosher... strange but true, I guess.

 

[Coyote machine]

50 amp rated stove goes to 58 amp draw and the 60 amp breaker does not trip.... house burns down.
50 amp rated stove is hooked to 50 amp receptacle and correct wiring to 50 amp breaker. Stove creates 58 amp draw on circuit - breaker trips and saves house and occupants.
Ranges sold today do not come with wire kit to hook to the wall receptacle. Owner/electrician needs to match range rating to receptacle/house wiring and correct breaker before/during range install.
Problem solved. Case closed. Next item.

 

[murphy1244]

50 amp rated stove goes to 58 amp draw and the 60 amp breaker does not trip.... house burns down.
50 amp rated stove is hooked to 50 amp receptacle and correct wiring to 50 amp breaker. Stove creates 58 amp draw on circuit - breaker trips and saves house and occupants.
Ranges sold today do not come with wire kit to hook to the wall receptacle. Owner/electrician needs to match range rating to receptacle/house wiring and correct breaker before/during range install.
Problem solved. Case closed. Next item.

When did they stop putting cords on them? I had to change out a cord one came with cause I was not allowed to use a extension cord.

 

[Coyote machine]

Years. Last range I bought through Sears, I told them which type of cord male prong I needed, to match up the cord to my existing receptacle, because of all the different types. I also made sure the amp rating of the range matched through from cord to receptacle to wire and finally the breaker. There are too many combos for them to supply a cord, so one has to specify what is needed.

 

[DarkBlack]

Hopefully some of you electricians that are well versed in code and all can help me out.

In the midst of selling my home and under contract. Home inspection was done, then I get the request for remedy sheet.

One of the things listed was "overfused condition".

Not sure what this meant. So no idea how to correct. So I called the inspector that did the inspection to get some clarification. He stated it was the range wiring.

There is a thing on the back of the range that reads just like this
"A UL listed power cord rated at 240v minimum, 40 amp or 50 amp power supply cord that is marked for use with nominal 1 3/8" diameter connection openings, with closed loop terminals and marked for use with ranges shall be used on this product."


Problem is, it is being fed with a 60a breaker and 6 ga wire. He said I need to change to a 40a or 50a breaker. Is that correct? I thought you size the breaker to the wire, and not the device?

Looking back at your first post, I see the range doesn't dictate the overcurrent device size.
I assume you put in a 50 amp breaker, and all's better with the inspector.

 

[LD1]

Looking back at your first post, I see the range doesn't dictate the overcurrent device size.
I assume you put in a 50 amp breaker, and all's better with the inspector.

Haven't yet. But will. Just havent had the time to get a breaker yet.

 

[hr3]

Hopefully some of you electricians that are well versed in code and all can help me out.

In the midst of selling my home and under contract. Home inspection was done, then I get the request for remedy sheet.

One of the things listed was "overfused condition".

He is correct.. The breaker is to be sized by the device being served,, 50 amp outlet 50 amp breaker...

Not sure what this meant. So no idea how to correct. So I called the inspector that did the inspection to get some clarification. He stated it was the range wiring.

There is a thing on the back of the range that reads just like this



Problem is, it is being fed with a 60a breaker and 6 ga wire. He said I need to change to a 40a or 50a breaker. Is that correct? I thought you size the breaker to the wire, and not the device?

The inspector is correct the breaker size is to be the same size or smaller than the device being served,,

 

[LD1]

It seems we are a bit split. Boy the NEC code sucks. Almost as bad as trailering laws :laughing: Seems the following believe I need to size the breaker according to THE LOAD

You can use a heavier wire, but the breaker has to match the load, not the wire. And like LD1 said, why get in a dither, spend a few bucks and take a few minutes to change the breaker out, problem solved, let the sale go forward

NO!! still needs to have the breaker changed. The breaker needs to be the size of the weakest link. In this senario it is the range at 40 amp.

NEC ARTICLE 422 APPLIANCES

422-4(a) Individual circuit The rating of an individual branch circuit shall not be less than the marked rating of the appliance or the marked rating of an appliance having combined loads in section 422-32 (appliances consisting of motors and other loads)
422-5 Branch circuit overload protection Branch circuits shall be protected in accordance with section240-3 (conductors shall be protected according to their ampacities).
If a protective device rating is marked on an appliance, the branch circuit overcurrent device rating shall not exceed the protective device rating marked on the appliance.

The inspector is correct the breaker size is to be the same size or smaller than the device being served,,

 

[LD1]

And the following believe I need to size it according to the circuit

I am an inspector (25 years). The 60 amp breaker is too high for the range outlet. It's listed to be used at up to 50A max.

I think what they are telling you is the actual outlet box is rated at 50 amps. It should be stamped right on the outlet what it is rated for. So if the outlet is rated at 50A you cant use a 60A breaker, simple enough.

The cord set that you plug in is rated 50A. The receptacle you plugged that cord into is listed for 50A max. So you can't install it on a 60A circuit. The NEC reference is Table 210.24 in the 2014 edition.

LD1 no you will not find it in the NEC that says a range must be 40A or 50A. What you will find is that the range receptacle can not be protected by more than a 50A breaker or fuse.

"snip"

He wrote up that the range circuit was not protected at proper ampacity.

In your stove case, what they are saying, is that the house's stove receptacle is not rated for the 60 amps that the wiring and breaker are. In other words the breaker, wiring and recepticle have to all be rated.

Very well could have been but now there is a 50amp receptacle in the picture which is why it can't have a 60amp breaker!

He can use a 50A breaker

Look at your receptacle. I bet it says 50A, if so put in a 50 amp breaker.

And you most certainly can plug a 40A range into a 50A receptacle/circuit. Yours even says 40A or 50A, so plug away.

But you do not have a 50A circuit until you change out the 60A breaker.

I would say that would be fine as it doesn't exceed what the circuit is rated at..50amps But as far as I know most range receptacles are rated at 50amps..thus the 60 amp breaker issue..the breaker would allow it to draw more than the receptacle was rated at..thus causing heat and possibly a fire..that would be my take BUT I am not an electrician or inspector!

 

[LD1]

At any rate, I had a 40A running the welder in the garage. It replaced the 60A that was on the range circuit.

My range doesnt actually specify what size to use. Rather just specify the "power cord" bust be 40 or 50A rated.

And at this point, if it didnt have that "or 50A" in there, I have no idea whether I would be allowed to plug it in to a 50A circuit? And not that it really matters though.