Branch Circuit

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resistance

Senior Member
Location
WA
I was in a debate about a tap per NEC T.220.55-Note 4. I believe I'm correct. reason the conversation started: We seen a house with a 40A branch circuit serving a range and one wall mounted oven. They did a tap at a remote junction box. I clearly argue that NEC 220.55 Note 4 is clear, and does not mention or permit an individual range circuit to serve any other load. Obviously the other person argues that the tap rule can be utilized regardless of the cooking appliances involved. Saying that a range can be considered two wall mounted ovens --based on a total the nameplate calculation:happysad:. In other words, he feels that if the range only required 8KW, then it's perfectly fine.
Your thoughts!!
 

iwire

Moderator
Staff member
Location
Massachusetts
Forget it, I don't need your thoughts!!!

Well you are getting them anyway, check out 210.19(A)(3) Exception 1. I think it shows that a range circuit can be tapped just not the way you saw it.


Exception No. 1: Conductors tapped from a 50-ampere
branch circuit supplying electric ranges, wall-mounted
electric ovens, and counter-mounted electric cooking units
shall have an ampacity of not less than 20 amperes and
shall be suffıcient for the load to be served. These tap conductors
include any conductors that are a part of the leads
supplied with the appliance that are smaller than the
branch-circuit conductors. The taps shall not be longer
than necessary for servicing the appliance.
 

RUWired

Senior Member
Location
Pa.
I was in a debate about a tap per NEC T.220.55-Note 4. I believe I'm correct. reason the conversation started: We seen a house with a 40A branch circuit serving a range and one wall mounted oven. They did a tap at a remote junction box.

The violation here is that the circuit needs to be a 50 amp circuit and the j-box needs to be as close as possible to the two units.

resistance said:
I clearly argue that NEC 220.55 Note 4 is clear, and does not mention or permit an individual range circuit to serve any other load. Obviously the other person argues that the tap rule can be utilized regardless of the cooking appliances involved. Saying that a range can be considered two wall mounted ovens --based on a total the nameplate calculation:happysad:. In other words, he feels that if the range only required 8KW, then it's perfectly fine.
Your thoughts!!

Since there is a range and a wall mount oven, this has to be treated as 2 appliances in table 220.55.

Rick
 

paul

Senior Member
Location
Snohomish, WA
Exception No. 1: Conductors tapped from a 50-ampere
branch circuit supplying electric ranges, wall-mounted
electric ovens, and counter-mounted electric cooking units
shall have an ampacity of not less than 20 amperes and
shall be suffıcient for the load to be served.

This sentence needs to be clarified. Are they talking about the tapped conductors that supply the ranges, ovens and cooking units or are they talking about the 50amp branch circuit that supplies those items? :?
 

RUWired

Senior Member
Location
Pa.
This sentence needs to be clarified. Are they talking about the tapped conductors that supply the ranges, ovens and cooking units or are they talking about the 50amp branch circuit that supplies those items? :?
They are saying a 50 amp circuit to anyone of those appliances is allowed to be tapped with a conductor rated not less than a 20 amps. including the conductors of the appliance.
 

John120/240

Senior Member
Location
Olathe, Kansas
Let's see if I understand; I have a built in oven & a seperate cooktop. Normally

I would use 8-3 w/g NM at 40 A for the oven; 10-3 w/g NM at 30 A for the

cooktop. So you can run one circuit & tap to both appliances ? Would it be

better to use 8-3 w/g NM for both appliances, that would alleviate OCPD

concerns ? What is the advantage to this setup ??:?:?
 

iwire

Moderator
Staff member
Location
Massachusetts
I think back in the day when many people only had four or six circuit 'main and range' fuse panels this was a real advantage.

Now you could still save a breaker and some wire.
 

iwire

Moderator
Staff member
Location
Massachusetts
Here is a handbook image about it.

21019NECHB.jpg
 

resistance

Senior Member
Location
WA
Well you are getting them anyway, check out 210.19(A) (3) Exception 1. I think it shows that a range circuit can be tapped just not the way you saw it.
I agree. I do not agree that an individual 40 amp circuit (Using #8NM) serving a range (requiring no less than 40 amps) can be tapped. In the case involving our situation. There were a couple violations that made this tap against code. 1. Conductor size. 2. OCPD size.



Let's see if I understand; I have a built in oven & a separate cooktop. Normally

I would use 8-3 w/g NM at 40 A for the oven; 10-3 w/g NM at 30 A for the

cooktop. So you can run one circuit & tap to both appliances ? Would it be

better to use 8-3 w/g NM for both appliances, that would alleviate OCPD

concerns ? What is the advantage to this setup ??
No you would be in violation. See 210.19(A)3, and T. 310.16 [2008 NEC].
Strangely enough—even the example picture iwire posted, we always see an example of ovens, and cooktops being tapped, but never a range—with an oven or cooktop!? To sound contradictory (with less regard to my initial post), I can say that a range (depending on the appliance) may need its own circuit.
 
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iwire

Moderator
Staff member
Location
Massachusetts
I agree. I do not agree that an individual 40 amp circuit (Using #8NM) serving a range (requiring no less than 40 amps) can be tapped. In the case involving our situation. There were a couple violations that made this tap against code. 1. Conductor size. 2. OCPD size.

I am not sure where I stand on the circuit size issue.

I don't see a conductor size issue.



No you would be in violation. See 210.19(A)3, and T. 310.16 [2008 NEC].
Strangely enough—even the example picture iwire posted, we always see an example of ovens, and cooktops being tapped, but never a range—with an oven or cooktop!? To sound contradictory (with less regard to my initial post), I can say that a range (depending on the appliance) may need its own circuit.

I don't think I agree with you at all here but I may not be following you correctly.
 

iwire

Moderator
Staff member
Location
Massachusetts
I think it is clear this applies to ranges, cooktops and ovens


210.19(A)(3) Household Ranges and Cooking Appliances. Branchcircuit
conductors supplying household ranges, wallmounted
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 83⁄4 kW or
more rating, the minimum branch-circuit rating shall be 40
amperes.

Exception No. 1: Conductors tapped from a 50-ampere
branch circuit supplying electric ranges, wall-mounted
electric ovens, and counter-mounted electric cooking units
shall have an ampacity of not less than 20 amperes and
shall be suffıcient for the load to be served. These tap conductors
include any conductors that are a part of the leads
supplied with the appliance that are smaller than the
branch-circuit conductors. The taps shall not be longer
than necessary for servicing the appliance.
 

resistance

Senior Member
Location
WA
@iwire:
The exception (from NEC 210.9A3) states: Tapped from a 50A branch circuit. So I see a problem with the conductor size [Per NEC T310.16], and OCPD size [per NEC T.310.16, and 210.9(A)3]. The install only had a #8 NM-b cable, with a 40A Breaker.

No you would be in violation. See 210.19(A)3, and T. 310.16 [2008 NEC].
Strangely enough?even the example picture iwire posted, we always see an example of ovens, and cooktops being tapped, but never a range?with an oven or cooktop!? To sound contradictory (with less regard to my initial post), I can say that a range (depending on the appliance) may need its own circuit. I don't think I agree with you at all here but I may not be following you correctly.
Don't see why you don't agree. Maybe I'm missing something?? I thought the code was clear?? Then again, I haven't been doing much of any electrical (due to the economy), so what the heck do i know.............LOL!!!
 

RUWired

Senior Member
Location
Pa.
No you would be in violation. See 210.19(A)3, and T. 310.16 [2008 NEC].
The size of the two appliances would need to be known first. The oven and cooktop kw are added and treated as 1 appliance. If the kw is over 12 kw then the 40 amp circuit is to small. If under 12 kw, then the 40 amp circuit is good, but the location of the j-box is important. The box has to be located between the two units and the taps can only be long enough to allow the appliances to be removed. If the cooktop is in the island away from the oven, the rule doesn't apply.

Rick
 

RUWired

Senior Member
Location
Pa.
The install only had a #8 NM-b cable, with a 40A Breaker.

!!!
I see it as the maximum run conductor is a 50 amp with a minimum 20 amp conductor. Article 210.23(C) and table 210.24 allow 40 and 50 amp circuits to be tapped with 12 awg.

Rick
 
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RUWired

Senior Member
Location
Pa.
I should say 210.23(C) allows 40 and 50 amp circuits for cooking appliance(S)...and table 210.24 allows the conductor sizes.

Rick
 

dana1028

Senior Member
... but the location of the j-box is important. The box has to be located between the two units and the taps can only be long enough to allow the appliances to be removed. If the cooktop is in the island away from the oven, the rule doesn't apply.Rick

"but the location of the j-box is important" - agreed

"The box has to be located between the two units" - disagree - handbook makes such an assertion, but the NEC makes no such stipulation.

"If the cooktop is in the island away from the oven, the rule doesn't apply" - agreed.
 

kwired

Electron manager
Location
NE Nebraska
The size of the two appliances would need to be known first. The oven and cooktop kw are added and treated as 1 appliance. If the kw is over 12 kw then the 40 amp circuit is to small. If under 12 kw, then the 40 amp circuit is good, but the location of the j-box is important. The box has to be located between the two units and the taps can only be long enough to allow the appliances to be removed. If the cooktop is in the island away from the oven, the rule doesn't apply.

Rick

Run 50 amp conductors to a j box near oven, tap to the oven, run 50 amp conductor to junction box in island near cooktop, tap to the cooktop.

The only conductors that are 'taps' are those that are lesser ampacity than the overcurrent device protecting them. Oven and cooktop wouldn not even have to be in same room.
 

dana1028

Senior Member
I should say 210.23(C) allows 40 and 50 amp circuits for cooking appliance(S)...and table 210.24 allows the conductor sizes.

Rick

This sounds logical and per the two referenced code section I think you could easily reach such a conclusion.

However, 210.19(A)(3), x-1 shows a 50A circuit is necessary for such a tap exception to be allowed. If T210.24 was 'the rule', why then was an exception created stipulating a 50A ckt. for such a tap?

I'm not disagreeing with the logic of your argument I'm just wondering if it is valid.
 
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