Range Wire Sizing

[don_resqcapt19]

Mike,

As I have asked more than one time could someone explain away these words that are found in 210.19(A)(3)
For ranges of 8? kW or more rating, the minimum branch-circuit rating shall be 40 amperes.
Am I as an electrical contractor or instructor supposed to say that they don?t exist?

The existence of those words doesn't change the previous words. I have no idea why they are even in the code as they serve no purpose.
Don

 

[jeff43222]

Now that we're all in agreement and everything's been cleared up...

Trouble maker. :lol:

I think that status was bestowed upon me when I started what turned into the longest thread ever. Of course, in this regard, I'm just an apprentice compared to my neighbor Al.

Would anyone care to venture an opinion as to what size circuit I should install for this 14.4 kW range?

Only one option run 3 AWG copper and tap the service conductors without any breaker. :wink:

Yeah, but #3 copper is expensive! I have some extra Cat-3 phone wire I'm not using. Can't I just use that? :wink:

I will think on your question and get back to you with a real answer or at least my opinion.

I can tell you that I would most likely run a 60 amp circuit for this 14.4 KW load but that is not code minimum.

The homeowner tells me he doesn't have plans to do any major cooking. I'm not sure why he bought such a whompin' range, though. I'm leaning toward installing a 50A circuit.

 

[iwire]

I have some extra Cat-3 phone wire I'm not using. Can't I just use that? :wink:

Maybe, but Cat 5E might provide better power quality for better tasting roasts. :lol:

 

[Gmack]

I think everyone is quoting "right" NEC here. But.

There is an example under 220.55 . Note 3, that calculates 3 household ranges in the same room that total 21kw.

Short answer = 48.3 A. Seems fine to me to hook all these ranges up this way according to demand.

I would not consider the OP for/as a maximum load to be served.

Apparently the OEM of the range is not worried about it either.

 

[jwelectric]

Bob you keep using the word Maximum and I can?t understand where you are coming up with this word.

I am quoting the section of the code as it is printed so please address that part that I am quoting. Once again the last sentence will modify the first sentence of a paragraph as outlined in the Style Manual.

I have not disputed anything written in 210.19(A)(3) I have only pointed out the last sentence which clearly makes the statement that a MINIMUM circuit of 40 amps for a range of 8 ? kw or more rating is all that is required.

I could care less if a 200 amp circuit was installed for a 20 amp cook top I am still waiting for someone to address just what is meant by the last sentence.

Can anyone explain the words of the last sentence as they are printed on that page?
:?:

 

[Gmack]

jw, sometimes we look/read the NEC with blinders on.

That "sentence" your quoting is not perfect because it is closed ended. It does not reference 220.55, which provides for larger connected loads which exceed this 40 A minimum.

I provided a reference from 220.55 which on "nameplates" alone added up to well over 85 A. The same book/Nec that quotes a minimum of 40 A that you site also requires a larger circuit of 48 A to service a 85 A, total connected load--->nameplates.

Would I wire 3 ranges, one cooktop, 2 wall mount with an 80 A breaker and circuit?

Hows that supposed to work here?

No. No electrician would/shouldnt do that. Rather we should "employ" demand.

Can we wire this same 21kW setup with a minimum 40A?

Same codebook says no.

 

[iwire]

Can anyone explain the words of the last sentence as they are printed on that page?
:?:

Apparently not. :lol:

I assume you still have a taste for crow? :lol:

 

[iwire]

Bob you keep using the word Maximum and I can?t understand where you are coming up with this word.

I find my words and their meanings in a dictionary.

Where did you find your definition of minimum? :lol:

Edit..Can't spell :roll:

 

[hardworkingstiff]

This thread has shown me that Article 220 has been redone in 2005 (a lot).

220.4 does not exist in 2005.

 

[George Stolz]

Mike, it says (paraphrasing) that a range that pulls 36 amps shall be on no less than a 40A branch circuit. No demanding it down to a 35 or 30 amp circuit is allowed.

Nothing more, nothing less.

We keep saying "maximum" because you're saying "minimum" and acting "maximum."

Just like I was looking right at the table's notes earlier and getting "every half kW is five percent" instead of "every kW is five percent." The 5% was shorting out some neurons in my head, and I was screwing up all kinds of math on account of it. You saw it clearly, and probably wondered what kind of herbs were in my tea when I wrote that. Being a nice guy you corrected me.

That sensation is the same one we're having now, Mike. We're watching your neurons freaking out, and waiting for the short to clear.

Minimum = minimum, not minimum = maximum.

When you're done, I've got some BBQ sauce left over from my episode yesterday, you're welcome to it.

 

[iwire]

This thread has shown me that Article 220 has been redone in 2005 (a lot).

I think the info has not changed but it is all moved around.

Find 2002 220.4 as 2005 220.18

 

[jwelectric]

See no one has yet addressed the last sentence of 210.19(A)(3).
I have heard a lot of opinion but as yet not one word as to the last sentence of this section.
Either you can or you can?t explain these words and if you can?t then I stand on what I have been saying all along.

The words are as clear as day that this is addressing the minimum circuit size as the entire Article of 210 does.

ARTICLE 210 Branch Circuits
I. General Provisions
210.1 Scope.
This article covers branch circuits except for branch circuits that supply only motor loads, which are covered in Article 430. Provisions of this article and Article 430 apply to branch circuits with combination loads.
II. Branch-Circuit Ratings
210.19 Conductors ? Minimum Ampacity and Size.
(A)(3) (3) Household Ranges and Cooking Appliances. Branch-circuit conductors supplying household ranges, wall-mounted ovens, counter-mounted cooking units, and other household cooking appliances shall have an ampacity not less than the rating of the branch circuit and not less than the maximum load to be served.

For ranges of 8? kW or more rating, the minimum branch-circuit rating shall be 40 amperes.

Now you can throw anything and everything you want into this debate but not one person (other than me) has addressed this sentence. All I am saying is that the smallest circuit that can be installed on ANY range rated MORE than 8 ? kw is a 40 ampere circuit

Article 210 address branch circuits and 210.19 addresses the MINIMUM size as outlined in (A)(3) is 40 amps for a range of 8 ? or more rating.

As the NEC itself is a minimum standard I can?t for the life of me see where you all are coming up with a maximum branch circuit rating. I have not made a mention to the maximum and I never will as it would be out of context of the code itself.

Now address the last sentence of 210.19(A)(3) as this is the only sentence that I am talking about.
What is meant by 8 ? or more rating?

 

[iwire]

See no one has yet addressed the last sentence of 210.19(A)(3).
I have heard a lot of opinion but as yet not one word as to the last sentence of this section.
Either you can or you can?t explain these words and if you can?t then I stand on what I have been saying all along.

That tells me you have not given us the courtesy of actually reading and paying attention to all our posts.

the minimum branch-circuit rating shall be 40 amperes.

Yes Mike the minimum not the maximum. :lol:

I take that to mean that a 8.75 KW range (36 amps @ 240) will have a minimum branch circuit rating of 40 amps.

However a 14 KW range (58 amps @ 240) will need a larger than the minimum 40 amp branch circuit.

Mike , You will have to supply a larger circuit if the maximum (demand ) load is higher or the name plate rating is higher.
Rick

First Atricle 220 has nothing to do with the selection of conductor size. The rule that applies is 210.19(A)(3), but you have apply all of the rule, not just the last part of it.

If the load is over 9.6 kW you can't use the minimum branch circuit rating.
Don

The existence of those words doesn't change the previous words. I have no idea why they are even in the code as they serve no purpose.
Don

Mike, it says (paraphrasing) that a range that pulls 36 amps shall be on no less than a 40A branch circuit. No demanding it down to a 35 or 30 amp circuit is allowed.

Nothing more, nothing less.

Bob, you can add me to the list. I can see this being a 10 page post but I'm not sure why that is so. The articles that you've posted seem quite clear.

Mike if I had all those names lined up against me and no one had posted support I would reconsider my position.

Not saying I would change my view just would ask why all these folks feel different than I do.

 

[Gmack]

jw, try answering your question yourself.

If you had a27kW single or combination range allowed as one range in the same room [NEC].

What size circuit would you install?

BTW. I did address your "sentence" from the NEC.

Why dont you address 220.55?

 

[Gmack]

Slow down here Iwire.

don_resqcapt19 wrote:
First Atricle 220 has nothing to do with the selection of conductor size. The rule that applies is 210.19(A)(3), but you have apply all of the rule, not just the last part of it.

If the load is over 9.6 kW you can't use the minimum branch circuit rating.
Don

NEC 2005 220.55

4. Branch-Circuit Load. It shall be permissible to calculate the branch-circuit load for one range in accordance with Table 220.55. The branch-circuit load for one wall-mounted oven or one counter-mounted cooking unit shall be the nameplate rating of the appliance. The branch-circuit load for a counter-mounted cooking unit and not more than two wall-mounted ovens, all supplied from a single branch circuit and located in the same room, shall be calculated by adding the nameplate rating of the individual appliances and treating this total as equivalent to one range.

This has everything to do with branch circuit conductor size.

 

[iwire]

Slow down here Iwire.

don_resqcapt19 wrote:
First Atricle 220 has nothing to do with the selection of conductor size. The rule that applies is 210.19(A)(3), but you have apply all of the rule, not just the last part of it.

If the load is over 9.6 kW you can't use the minimum branch circuit rating.
Don

Gmack I am not Don, you can tell Don to slow down but that is generally a bad choice. :lol:

I have 'known' Don for about 3 or 4 years now and he is very rarely mistaken. 8)

That aside go ahead and use the table for the 27 KW range in your question, we still end up above a 40 amp load.

 

[Gmack]

georgestolz wrote:
Mike, it says (paraphrasing) that a range that pulls 36 amps shall be on no less than a 40A branch circuit. No demanding it down to a 35 or 30 amp circuit is allowed.

Nothing more, nothing less.

This is not correct.

3. Over 1 3/ 4 kW through 8 3/ 4 kW. In lieu of the method provided in Column C, it shall be permissible to add the nameplate ratings of all household cooking appliances rated more than 1 3/ 4 kW but not more than 8 3/ 4 kW and multiply the sum by the demand factors specified in Column A or B for the given number of appliances. Where the rating of cooking appliances falls under both Column A and Column B, the demand factors for each column shall be applied to the appliances for that column, and the results added together.

NEC does not require a 40 A minimum below 8 3/4 kw.

 

[Gmack]

Iwire, you "quoted Don.

Yes?

I dont know what your getting at.

I have stated all day that we get above the 40 A minimum.

Have "you" been listening?

 

[iwire]

georgestolz wrote:
Mike, it says (paraphrasing) that a range that pulls 36 amps shall be on no less than a 40A branch circuit. No demanding it down to a 35 or 30 amp circuit is allowed.

Nothing more, nothing less.

This is not correct..

NEC does not require a 40 A minimum below 8 3/4 kw.

Gmack give us a break :roll: George said he was paraphrasing and we all know just as he does the discussion in this thread has to do with ranges 8.75 KW and above.

 

[iwire]

By the way, if you want to quote try this button

at the top of the post you want to quote.