Tapping off of a 240V dryer circuit for a 120V outlet: What section of the code?

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david luchini

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How about this situation:

120 volt 20 amp branch circuit feeding receptacle outlets, 12 AWG conductor. We decide we want to add a lighting outlet but for whatever reason we want to use 14 AWG conductor, so we come from one of the receptacle outlets to a 15 amp breaker and continue on with 14 AWG for the lighting outlet, switch(es) etc. Is this allowed by NEC or not, assuming it is not a SABC or some other dedicated circuit that would otherwise prohibit the lighting outlet even if it were supplied with 12 AWG.

No, this is not allowed. You cannot create a "new" branch circuit from an existing branch circuit. Your 20A branch c/b will no longer be the "final overcurrent device" protecting the circuit. Your #12 conductors between the 20A c/b and the 15A c/b will be, by definition, feeder conductors.

But there is no reason for the 15A breaker. You could run a #14 awg tap from your 20A branch circuit to a lighting outlet without the 15A breaker if you comply with 210.19(A)(4) ex. no. 1.
 

ELA

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Thanks to all for your responses. I was asked this question and my response was that I thought it would be a code violation unless you added reduced overcurrent protection.
In addition I thought it was just a bad idea but I could not point definitively to a code section that disallowed it. So I was interested in knowing if there was a definitive code section addressing this.

After reviewing the sections you all have mentioned I still feel the same. Even if you could apply a tap rule I would not feel comfortable with supplying a 15 or 20A receptacle to a 30A+ feeder (without additional protection), that's just an opinion though.

Maybe if it was just a case as in 210.19(A) (4) (c) that was dedicated outlet to a load, but was not a receptacle. I do not like the thought that a person could connect a cord to the receptacle (without a lower OCP).

From what I have read I now feel that it could be allowed if additional reduced overcurrent protection is added. I still do not like the idea myself though.

I am pretty weak when it comes to code so I appreciate your knowledge.
Isn't there also a concern about mixing general use receptacles ( on the same circuit and close to) with a relatively large motor such as that inside of a dryer as well?
 

david luchini

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From what I have read I now feel that it could be allowed if additional reduced overcurrent protection is added. I still do not like the idea myself though.

No, this is not correct. You cannot provide additional circuit overcurrent protection when tapping from a branch circuit.

I am pretty weak when it comes to code so I appreciate your knowledge.
Isn't there also a concern about mixing general use receptacles ( on the same circuit and close to) with a relatively large motor such as that inside of a dryer as well?

You may be thinking of 210.23(A)(1)&(2) and 210.23(B).
 

david luchini

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So what rule prohibits receptacles on feeders (a 30A receptacle on a 30A feeder in this case)?

A receptacle is an "outlet" by definition (and more specifically a "receptacle outlet" by definition.)

A Branch Circuit is the circuit conductors between the final overcurrent device protecting the circuit and the outlet(s), by definition.

A Feeder is the circuit conductors between the service equipment...and the final branch-circuit overcurrent device, by definition.

Service---Feeder---Branch Circuit---Outlet. Seems pretty clear to me.
 

ELA

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Hi David,

You could take the existing dryer branch circuit and provide a new branch overcurrent device near the dryer, thereby making the circuit from the panel to the new branch OCPD a feeder, and then tap the feeder. But as described, tapping a branch circuit to feed a receptacle, that is not permitted by code.

I thought that you were saying it would be ok in the above? Or were you saying only if the Dryer outlet were eliminated?
 

david luchini

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From what I have read I now feel that it could be allowed if additional reduced overcurrent protection is added. I still do not like the idea myself though.

I thought that you were saying it would be ok in the above? Or were you saying only if the Dryer outlet were eliminated?

Maybe I didn't understand your previous post, but the word "reduced" implied to me you wanted to connect a 20A c/b to the 30A branch circuit to feed a 20A receptacle. You cannot do that.

What I suggest earlier was to take the 30A branch circuit for the dryer, and provide an additional 30A c/b at the dryer location. This would make the circuit from the panel to the c/b at the dryer a feeder. You could then tap the feeder and provide a 20A c/b for the 20A receptacle. Hope this is clear.
 

kwired

Electron manager
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Thanks to all for your responses. I was asked this question and my response was that I thought it would be a code violation unless you added reduced overcurrent protection.
In addition I thought it was just a bad idea but I could not point definitively to a code section that disallowed it. So I was interested in knowing if there was a definitive code section addressing this.

After reviewing the sections you all have mentioned I still feel the same. Even if you could apply a tap rule I would not feel comfortable with supplying a 15 or 20A receptacle to a 30A+ feeder (without additional protection), that's just an opinion though.

Maybe if it was just a case as in 210.19(A) (4) (c) that was dedicated outlet to a load, but was not a receptacle. I do not like the thought that a person could connect a cord to the receptacle (without a lower OCP).

From what I have read I now feel that it could be allowed if additional reduced overcurrent protection is added. I still do not like the idea myself though.

I am pretty weak when it comes to code so I appreciate your knowledge.
Isn't there also a concern about mixing general use receptacles ( on the same circuit and close to) with a relatively large motor such as that inside of a dryer as well?

I think there is no question that 15 or 20 amp overcurrent protection would be required, the issue that has not clearly been solved is whether or not the dryer circuit can have this load tapped from it.

The motor in a typical electric clothes dryer is not a very big motor, maybe 1/3 -1/2 HP at the most. The heating elements in the dryer are the major load of the appliance.
 

kwired

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Sorry but I still have not seen a code section that says this can not be done.

210.19 has been mentioned but IMO does not apply. That section is not about a tap that will end at an overcurrent device.

The next best thing that has been brought up is the definitions of feeder and branch circuit. I see some logic to going with that, but where does it say a 30 amp receptacle can not be protected by a 30 amp overcurrent device, or can not be on a multioutlet/multiload circuit. The 30 amp receptacle still has proper overcurrent protection, but we no longer meet the definition of branch circuit or the definition of feeder. Does it strictly have to be a feeder or a branch circuit? If yes, tell us why.
 

Smart $

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This would only be compliant if you first turn the dryer branch circuit into a feeder.
Not 100% correct. I agree with you regarding feeder vs. branch circuit distinction.

The only compliant way (short of installing a subpanel) is to use supplemental OCP... but any conductor on its line side has to be of an ampacity equal or greater than that required for this "dryer plus 120V receptacle outlet" branch circuit... and thus not be either a branch or feeder tap.
 
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david luchini

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Sorry but I still have not seen a code section that says this can not be done.

210.19 has been mentioned but IMO does not apply. That section is not about a tap that will end at an overcurrent device.

210.19, ex. is about "Branch circuit taps." If you are going to tap a branch circuit, you have to follow the rules therein. The only rules for taps ending at an ocpd are the ones for feeder taps. But in the example, it is not a feeder being tapped, it is branch circuit, so the feeder tap rules don't apply. It seems fairly simple to me.

The next best thing that has been brought up is the definitions of feeder and branch circuit. I see some logic to going with that, but where does it say a 30 amp receptacle can not be protected by a 30 amp overcurrent device, or can not be on a multioutlet/multiload circuit. The 30 amp receptacle still has proper overcurrent protection, but we no longer meet the definition of branch circuit or the definition of feeder. Does it strictly have to be a feeder or a branch circuit? If yes, tell us why.

The definitions of "branch circuit" and "feeder" in given in Article 100 of the code. Why do you feel that you can just ignore the definitions. By definition, a circuit can't be both a feeder and a branch circuit.

But let's try this approach instead. In Article 210 "Branch Circuits" you will find quite a few references to "Outlets" (eg, 210.21.) This is because outlets are connect to branch circuits. You will not find the word "Outlet" in Article 215 "Feeders," except for in one of the FPNs. This is because outlets are NOT connected to feeders.
 

david luchini

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Not 100% correct. I agree with you regarding feeder vs. branch circuit distinction.

The only compliant way (short of installing a subpanel) is to use supplemental OCP... but any conductor on its line side has to be of an ampacity equal or greater than that required for this "dryer plus 120V receptacle outlet" branch circuit... and thus not be either a branch or feeder tap.

No, that is not correct. We have already looked at this possibility.

If the fuse is intended to protect the circuit conductors then it is not a Supplementary OCPD. A Supplementary OCPD is a device intended to provide limited overcurrent protection for specific applications and utilization equipment such as luminaires and appliances.

Per 240.21, a supplementary OCPD shall not be used as a substitute for required branch circuit OCPDs, or in place of the required branch circuit protection. You can't create a new branch circuit from an existing branch circuit.

A supplemental OCP cannot be used as a substitute for required branch circuit protection, and supplemental OCPs are only allowed to provide limited ocp for specific applications and utilization equipment. A supplemental OCPD cannot be used to provide protection for the smaller conductors which are tapped from the original branch circuit.
 

david luchini

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The only compliant way (short of installing a subpanel) is to use supplemental OCP... but any conductor on its line side has to be of an ampacity equal or greater than that required for this "dryer plus 120V receptacle outlet" branch circuit... and thus not be either a branch or feeder tap.

I may have misunderstood your point. Are you suggesting splicing off the #10s of the 30A dryer circuit, running #10 to a 20A fuse, and then running #10 to a 20A receptacle? You are correct that this is neither a branch circuit or feeder tap, however, it would violate 210.21(B)(3).
 

kwired

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210.19, ex. is about "Branch circuit taps." If you are going to tap a branch circuit, you have to follow the rules therein. The only rules for taps ending at an ocpd are the ones for feeder taps. But in the example, it is not a feeder being tapped, it is branch circuit, so the feeder tap rules don't apply. It seems fairly simple to me.



The definitions of "branch circuit" and "feeder" in given in Article 100 of the code. Why do you feel that you can just ignore the definitions. By definition, a circuit can't be both a feeder and a branch circuit.

But let's try this approach instead. In Article 210 "Branch Circuits" you will find quite a few references to "Outlets" (eg, 210.21.) This is because outlets are connect to branch circuits. You will not find the word "Outlet" in Article 215 "Feeders," except for in one of the FPNs. This is because outlets are NOT connected to feeders.

The taps mentioned in 210.19 are not the same thing as the tap mentioned in the OP of this thread. Those taps are fixed loads such as ranges, ovens, cooktops, or taps off lighting circuits to individual luminaires, all of which are permitted to tap off the circuit that supplies them without additional overcurrent protection. The condition of what the OP is asking about is reducing overcurrent protection on an extended smaller conductor from the original circuit. It is similar condition to feeder taps mentioned in 240.21.

I do not disagree with the definition of feeder or branch circuit. If the circuit meets some of the conditions of both I don't see how you can say it is impossible to be both, it is just a situation we do not have an official name for. It is definately not entirely one or the other on the 30 amp portion of the circuit. The 15 or 20 amp portion does fit definition of branch circuit.

Overcurrent protection rules for the conductors and for the receptacles have not been broken, so I don't see any real danger. I am not suggesting it is a good design practice but see no code violation either.

Put it this way - I don't see where there is a requirement that receptacles, luminaires, or other loads are required to be on a branch circuit, but rather the conductors supplying those items by definition become branch circuit conductors - usually.
 

david luchini

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The taps mentioned in 210.19 are not the same thing as the tap mentioned in the OP of this thread. Those taps are fixed loads such as ranges, ovens, cooktops, or taps off lighting circuits to individual luminaires, all of which are permitted to tap off the circuit that supplies them without additional overcurrent protection. The condition of what the OP is asking about is reducing overcurrent protection on an extended smaller conductor from the original circuit. It is similar condition to feeder taps mentioned in 240.21.

The circuit the OP was attempting to tap is a BRANCH CIRCUIT. Branch circuit taps are addressed in 210.19. Any tap from a branch circuit MUST comply with 210.19.

240.21(B) says "conductors shall be permitted to by tapped, without overcurrent protection at the to a FEEDER..." The circuit in the OP is not a feeder. 240.21(B) does not apply to a tap from a branch circuit.

I do not disagree with the definition of feeder or branch circuit. If the circuit meets some of the conditions of both I don't see how you can say it is impossible to be both, it is just a situation we do not have an official name for. It is definately not entirely one or the other on the 30 amp portion of the circuit. The 15 or 20 amp portion does fit definition of branch circuit.

These two statements in red are contradictory. If you agree that a feeder is all of the circuit conductors between the service equipment and the final BRANCH CIRCUIT ocpd, and you agree that a branch circuit is the circuit conductors between the final BRANCH CIRCUIT ocpd and the outlets, then you cannot believe that a circuit can be both. A circuit cannot be "before the branch circuit OCPD and "after" the branch circuit at the same time. If the 15 or 20 amp portion fits the definition of a branch circuit, then the conductors before the 15 or 20A ocpd fit the definition of "feeder."

Overcurrent protection rules for the conductors and for the receptacles have not been broken, so I don't see any real danger. I am not suggesting it is a good design practice but see no code violation either.

Put it this way - I don't see where there is a requirement that receptacles, luminaires, or other loads are required to be on a branch circuit, but rather the conductors supplying those items by definition become branch circuit conductors - usually.

Overcurrent protection is found in Article 240. Article 210 applies to Branch Circuits. Article 215 applies to Feeders. Branch Circuit and Feeders must comply with 210 and 215 respectively, as well as 240. "Outlets" are only found in Art. 210, not in Article 215. The definitions say that outlets can only be connect to branch circuits. The requirements that receptacle OUTLETS, luminaire OUTLETS, or other load OUTLETS be on branch circuits are found in Art. 210 and in the definition of branch circuit.

Lets try this. I've pointed out in Art. 210 where is talks about Outlets (210.21) and the definition of "Branch Circuit" which mentions Outlets. Can you point out anywhere in Art. 215 or the definition of "Feeder" where it mentions connection Outlets to a feeder?
 
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kwired

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The circuit the OP was attempting to tap is a BRANCH CIRCUIT. Branch circuit taps are addressed in 210.19. Any tap from a branch circuit MUST comply with 210.19.

240.21(B) says "conductors shall be permitted to by tapped, without overcurrent protection at the to a FEEDER..." The circuit in the OP is not a feeder. 240.21(B) does not apply to a tap from a branch circuit.



These two statements in red are contradictory. If you agree that a feeder is all of the circuit conductors between the service equipment and the final BRANCH CIRCUIT ocpd, and you agree that a branch circuit is the circuit conductors between the final BRANCH CIRCUIT ocpd and the outlets, then you cannot believe that a circuit can be both. A circuit cannot be "before the branch circuit OCPD and "after" the branch circuit at the same time. If the 15 or 20 amp portion fits the definition of a branch circuit, then the conductors before the 15 or 20A ocpd fit the definition of "feeder."



Overcurrent protection is found in Article 240. Article 210 applies to Branch Circuits. Article 215 applies to Feeders. Branch Circuit and Feeders must comply with 210 and 215 respectively, as well as 240. "Outlets" are only found in Art. 210, not in Article 215. The definitions say that outlets can only be connect to branch circuits. The requirements that receptacle OUTLETS, luminaire OUTLETS, or other load OUTLETS be on branch circuits are found in Art. 210 and in the definition of branch circuit.

Lets try this. I've pointed out in Art. 210 where is talks about Outlets (210.21) and the definition of "Branch Circuit" which mentions Outlets. Can you point out anywhere in Art. 215 or the definition of "Feeder" where it mentions connection Outlets to a feeder?

If you connect the line side of the 15/20 amp overcurrent device with a 30 amp conductor by definition do you still have a tap?

The 30 amp is a branch circuit for the dryer. It is also a feeder for the 15/20 amp branch circuit. The definitions are what they are I see no place that prohibits a circuit or portion of a circuit from fitting both definitions.

A service that feeds a single load could have a similar controversy. Isn't the Service disconnect both a service disconnect and a branch circuit overcurrent device in this situation?
 

david luchini

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If you connect the line side of the 15/20 amp overcurrent device with a 30 amp conductor by definition do you still have a tap?

No, this is not a tap.

The 30 amp is a branch circuit for the dryer. It is also a feeder for the 15/20 amp branch circuit. The definitions are what they are I see no place that prohibits a circuit or portion of a circuit from fitting both definitions.

It cannot be both. A branch circuit is the conductors between the FINAL overcurrent device and the load. When you add your 20A OPCD to the dryer circuit, the 30A OCPD is no longer the FINAL overcurrent device in the circuit. A branch circuit is NOT the conductors between the "FINAL" ocpd and another "MORE FINAL THAN THE FIRST FINAL OCDP" ocpd.

The definitions of branch circuit and feeder are mutually exclusive. Feeders are everything up to the final OCPD and branch circuits are everything after the final OCPD. By their very definition, a circuit can't be both.

And what section allows an outlet to be connected to a feeder?


A service that feeds a single load could have a similar controversy. Isn't the Service disconnect both a service disconnect and a branch circuit overcurrent device in this situation?

This isn't a similar controversy at all. In what you have described, there is no feeder.
 
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