Range - 3W requirement

[lielec11]

I know this was changed recently in the code... where an electric range is required to be served by a 3W+G branch circuit (i.e. 14-50R) instead of a 2W+G branch circuit (i.e. 6-20R). I can't seem to remember which part of the code though. Can someone point me to the section?

 

[dkidd]

250.140 Frames of Ranges and Clothes Dryers.

 

[lielec11]

250.140 Frames of Ranges and Clothes Dryers.

I still don't quite understand how this requires 2 hots, a neutral, and a ground. Why can't I simply run 2 hots and an EGC sized per 250.122?

 

[GoldDigger]

I still don't quite understand how this requires 2 hots, a neutral, and a ground. Why can't I simply run 2 hots and an EGC sized per 250.122?

You can run two hots plus an EGC if the range does not make use of the neutral.
What you cannot do, for new construction, is use a combined neutral/EGC to carry normal operating current.

 

[lielec11]

You can run two hots plus an EGC if the range does not make use of the neutral.
What you cannot do, for new construction, is use a combined neutral/EGC to carry normal operating current.

I get that, so...

240V, 1-phase electric range: 2W+G, 6-xxR receptacle (xx is amperage)
120/240,1-phase electric range: 3W+G, 14-xxR receptacle
120V, 1-phase gas range: 2W+G, 5-20R receptacle

sound about right?

 

[curt swartz]

You can run two hots plus an EGC if the range does not make use of the neutral.
What you cannot do, for new construction, is use a combined neutral/EGC to carry normal operating current.

And you have never been allowed to use the EGC as the Neutral.

If the range does not require a Neutral you are not required to run one. I have never seen a residential range that doesn't require a neutral.

 

[GoldDigger]

And you have never been allowed to use the EGC as the Neutral.
....

True, but you once were allowed to use the neutral as an EGC. A small but significant difference.
If the connector designates a pole for only one of the two, and you are in a grandfathered situation where you do not need a separate EGC, and you need a neutral you must use a connector that designates a neutral pole.

 

[Dennis Alwon]

I still don't quite understand how this requires 2 hots, a neutral, and a ground. Why can't I simply run 2 hots and an EGC sized per 250.122?

250.140 states

250.140 Frames of Ranges and Clothes Dryers. Frames
of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction boxes
that are part of the circuit for these appliances shall be
connected to the equipment grounding conductor in the
manner specified by 250.134 or 250.138.

250.134 requires an equipment grounding conductor that does not carry current

Unless grounded by connection to the grounded circuit conductor as
permitted by 250.32, 250.140, and 250.142, non–current carrying
metal parts of equipment, raceways, and other enclosures,
if grounded, shall be connected to an equipment
grounding conductor by one of the methods specified in
250.134(A) or (B).

 

[lielec11]

250.134 requires an equipment grounding conductor that does not carry current

Right but my question really was about the neutral. It doesn't stipulate that I MUST run a neutral as well. I can get 240V from 2 hots, and run an EGC as required. Where does it say I must use a 3W+G branch circuit/plug?

 

[Dennis Alwon]

Right but my question really was about the neutral. It doesn't stipulate that I MUST run a neutral as well. I can get 240V from 2 hots, and run an EGC as required. Where does it say I must use a 3W+G branch circuit/plug?

It doe

sn't say you must use a neutral but if the range requires a neutral you cannot use the equipment grounding conductor. Therefore you must run a neutral in those cases. There are ranges that are straight 240v but if they are marked 120/240v then you need a neutral

 

[user 100]

Right but my question really was about the neutral. It doesn't stipulate that I MUST run a neutral as well. I can get 240V from 2 hots, and run an EGC as required. Where does it say I must use a 3W+G branch circuit/plug?

As said above, if the appliance doesn't require a neutral, you don't need to pull one.

250.140 says you must have an egc, that you cannot use a neutral to bond the frame of the appliance.

 

[lielec11]

It doe

sn't say you must use a neutral but if the range requires a neutral you cannot use the equipment grounding conductor. Therefore you must run a neutral in those cases. There are ranges that are straight 240v but if they are marked 120/240v then you need a neutral

OK just wanted clarification, thanks again....