6/3 nm cable for stove

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You want to cover all the possible cases, pipe it in or use copper 6/3 SE cable (it gets you the 75C column). You can then do 60A if you need to. Can't recall any residential stoves I've seen that need more than that.
 
Jpflex said:
I was referring to this:

4. Calculating the branch-circuit load for one range in accordance with Table 220.55 shall be permitted.
5. The branch-circuit load for one wall-mounted oven or one counter-mounted cooking unit shall be the nameplate rating of the appliance.
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And a branch circuit to a range can use the table for demand load.

So could a branch circuit supplying both a wall mounted oven and a counter mounted cooking unit.

A single range of no more than 12 kW rating you are allowed to apply a demand load of 8 kW - many put those on 8 AWG and a 40 amp breaker though technically a 35 amp breaker should be acceptable. They almost never draw enough current to trip a 40 amp breaker. They possibly might draw more than 40 amps at times, like if you turned every element on at same time from cold start, but wont draw that long enough time to trip the breaker
 
kwired said:
And a branch circuit to a range can use the table for demand load.

So could a branch circuit supplying both a wall mounted oven and a counter mounted cooking unit.

A single range of no more than 12 kW rating you are allowed to apply a demand load of 8 kW - many put those on 8 AWG and a 40 amp breaker though technically a 35 amp breaker should be acceptable. They almost never draw enough current to trip a 40 amp breaker. They possibly might draw more than 40 amps at times, like if you turned every element on at same time from cold start, but wont draw that long enough time to trip the breaker
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I have thought this lower demand load from the table was to be added to feeders or service conductors? But not the conductor for the stove.

I understand that a stove may not exceed or reach the conductors ampacity unless all stoves and oven are on simultaneously but this may practically happen during thanksgiving etc
 
roger said:
The title of article 220 is "Branch-Circuit, Feeder, and Service Calculations" but Part III is narrowed down to "Feeder and Service Load Calculations"
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See Post #33. This portion of Part III is referenced directly from Part II, because it has allowances for Branch Circuit Load Calculations.

Cheers, Wayne
 
tthh said:
You want to cover all the possible cases, pipe it in or use copper 6/3 SE cable (it gets you the 75C column). You can then do 60A if you need to. Can't recall any residential stoves I've seen that need more than that.
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Ok I’m just trying to understand the proper way to size applications to code since I plan to take my test for journeyman’s license as soon as I reach 4,000 hours of work experience. I have close to 3/4 hour requirement
 
Jpflex said:
I did confront them on the challenge of me sizing a stove cable before I know it’s watts/ KVA.

If I go large 6/3 and the stove is small watts then a larger 50 i breaker and 6/3 will be a violation and won’t protect the stove, fire hazard snd will violate code
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What makes you think 6-3 can't be used on a lesser wattage/amperage?
What would make it a fire hazard?
What is the code violation?
 
Little Bill said:
What makes you think 6-3 can't be used on a lesser wattage/amperage?
What would make it a fire hazard?
What is the code violation?
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Over sizing a breaker and branch circuit to a stove risk problems associated with overload. If the stove or fixed appliance for what ever reason begins to draw substantially more current than it’s listed nameplate then a breaker too large will not shut it off

I had a rice cooker that stayed on over the weekend years ago but was shut off due to what I believe was the breakers overload properties. The rice cooker has no short circuit but was obviously on continuous (over 3 hours)
 
Jpflex said:
Over sizing a breaker and branch circuit to a stove risk problems associated with overload. If the stove or fixed appliance for what ever reason begins to draw substantially more current than it’s listed nameplate then a breaker too large will not shut it off

I had a rice cooker that stayed on over the weekend years ago but was shut off due to what I believe was the breakers overload properties. The rice cooker has no short circuit but was obviously on continuous (over 3 hours)
Click to expand...
A stove will draw only 10 amps if you're only uses 1 burner which you are 90% of the time. It's listed for 50 amp outlets so you can use it on a 50 amp circuit.
 
Jpflex said:
I have thought this lower demand load from the table was to be added to feeders or service conductors? But not the conductor for the stove.

I understand that a stove may not exceed or reach the conductors ampacity unless all stoves and oven are on simultaneously but this may practically happen during thanksgiving etc
Click to expand...
Note 4 in 2017 allows you to use the table for demand for a single range. Sounds like from what others said this has changed in 2020 or 2023 but I think the allowance to use that demand value is still there somehow.
 
Jpflex said:
However, do I size wire for stove based on lower VA stove demand based on table or base cable size on actual stove nameplate ampere?
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You are looking to size for a particular stove? What happens when the next owner brings their stove? Unless you have a nameplate, wire to "normal" stove of your area. That has always been a 50 amp circuit for over 70 years around here. Only thing changed is 4 wires instead of three wires back then to the crowsfoot 50 amp receptacle.

If building a house for a specific stove then you need the nameplate. When has that happened? Only for 1% of mansions.... Of course the owners do not cook, but have caterers, gotta look like a rich kitchen in case friends stop by!😄
 
Jpflex said:
I have thought this lower demand load from the table was to be added to feeders or service conductors? But not the conductor for the stove.
Click to expand...

That would be the sensible understanding, and the way just about any other load would be figured.

For a normal load, you would size the branch circuit based on the actual load rating, and then use the various diversity and sizing factors to permit a smaller value to be used on an upstream feeder.

But stoves are treated differently, and the diversity factors that generally apply only to feeders also get applied to the stove branch circuit.

Jpflex said:
I understand that a stove may not exceed or reach the conductors ampacity unless all stoves and oven are on simultaneously but this may practically happen during thanksgiving etc
Click to expand...

Even than, I think this is unlikely. Remember that the oven/stove is really a collection of separate heating elements, each with its own control.

For every element to be on at full power at exactly the same time, you would have to start with a cold stove, turn every burner on to full, put something massive into the cold oven, and then set it for a high temperature. This is possible, but the same unlikely possibility applies to every diversity factor in the code.

Jon
 
Jpflex said:
Over sizing a breaker and branch circuit to a stove risk problems associated with overload. If the stove or fixed appliance for what ever reason begins to draw substantially more current than it’s listed nameplate then a breaker too large will not shut it off
Click to expand...

98% of what gets plugged in to a general purpose branch circuit falls into this category. It’s really not a problem. You’re way overthinking this.
 
To the OP. You should really stop using the word "Stove" when referring to NEC requirements. Many people call cooktops stoves.
If you have a single appliance (cooktop (counter mounted cooking unit) or oven) you are required to use the nameplate for sizing the branch circuits. If you have a range or cooktop and oven connected to the same branch circuit then you can apply the demand factors.
 
curt swartz said:
To the OP. You should really stop using the word "Stove" when referring to NEC requirements. Many people call cooktops stoves.
If you have a single appliance (cooktop (counter mounted cooking unit) or oven) you are required to use the nameplate for sizing the branch circuits. If you have a range or cooktop and oven connected to the same branch circuit then you can apply the demand factors.
Click to expand...
O ok 👍
 
Frank DuVal said:
You are looking to size for a particular stove? What happens when the next owner brings their stove? Unless you have a nameplate, wire to "normal" stove of your area. That has always been a 50 amp circuit for over 70 years around here. Only thing changed is 4 wires instead of three wires back then to the crowsfoot 50 amp receptacle.

If building a house for a specific stove then you need the nameplate. When has that happened? Only for 1% of mansions.... Of course the owners do not cook, but have caterers, gotta look like a rich kitchen in case friends stop by!😄
Click to expand...
Not a lot of "common ranges" over 12 kW which has an 8kW allowable demand in the table. But using the table and the notes you still can have up to a 16 kW range on a 40 amp circuit. Not going to find many at all with that much of a rating in a "common household range".
 
Jpflex said:
Over sizing a breaker and branch circuit to a stove risk problems associated with overload. If the stove or fixed appliance for what ever reason begins to draw substantially more current than it’s listed nameplate then a breaker too large will not shut it off

I had a rice cooker that stayed on over the weekend years ago but was shut off due to what I believe was the breakers overload properties. The rice cooker has no short circuit but was obviously on continuous (over 3 hours)
Click to expand...
I didn't mention OCP, I asked why you thought using 6-3 for a lower amperage/wattage was a danger or violation.
Example: OCP/Breaker = 40A, 6-3NM for the wiring
What is wrong with that?
 
I believe the OP had several things rolling around in his head...one of which was if the appliance doesn't need 40A, and it is on a 40A circuit, is the appliance being properly protected. The breaker isn't there to protect the appliance -- the breaker is there to protect the wiring.
 
There are some limitations on protection of the appliance regarding the overcurrent device not being excessively large. This is in 422.11. For a cook top, subpart (B) applies which limits branch circuits to 50A overcurrent devices and forces the manufacturer to subdivide the loads so 50A circuits work. Same rule applies to commercial cook tops in subpart (D) with an exception in (F)(2). So you should never need a circuit larger than 50A for a household range (but you may need more than one circuit) and 6-3 NM should almost always work even if bundled with other cables.

Part (E) is a general rule for non-motorized appliances limiting the circuit breaker to 150% of the appliance's rated current as long as the rated current is 13.3A or higher and there is no marked overcurrent device limit. For less than 13.3A nameplate, a 20A circuit is the limit.
 
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