Tap rule question

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Both definitions start off with the phrase "circuit conductors". This shows that the definitions are relative to a given circuit. For any single circuit, conductors will be either a feeder, or a branch circuit conductor, but not both.

However, since conductors can be part of multiple circuits, they can be branch circuit conductors for one circuit, and feeder conductors for another circuit. In the example diagram, Smart$ showed how in the circuit for the 60A outlet, the conductors A are branch circuit conductors. In my previous post, I showed how in the circuit for the 20A outlet, the conductors A are feeder conductors.

Cheers, Wayne
 
wwhitney said:
Both definitions start off with the phrase "circuit conductors". This shows that the definitions are relative to a given circuit. For any single circuit, conductors will be either a feeder, or a branch circuit conductor, but not both.

However, since conductors can be part of multiple circuits, they can be branch circuit conductors for one circuit, and feeder conductors for another circuit. In the example diagram, Smart$ showed how in the circuit for the 60A outlet, the conductors A are branch circuit conductors. In my previous post, I showed how in the circuit for the 20A outlet, the conductors A are feeder conductors.

Cheers, Wayne
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Conductors A are a single circuit with a single load current. They cannot be both feeder and branch circuit conductors.
 
Proof by blatant assertion and circular reasoning may be part of persuasive argumentation but they are not part of logic.
You cannot prove that the definitions do not overlap simply by asserting that conductors that fit one definition cannot therefore fit the other.
You have to look at the wording of each definition independently and see whether the conditions of that definition are met.
Examples have been given of conductors that meet both definitions. Whether or not the CMPs intended that or not and whether or not that causes problems elsewhere in the Code are relevant to the need for future changes, not the outcome of this argument.
 
david luchini said:
Conductors A are a single circuit with a single load current.
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Conductors A are not a circuit by themselves, they are just a pair of parallel wires. To complete a circuit, you need to have a connection at each end, typically a power source and a load. There are two circuits of which Conductors A are a part, namely the circuit to the 20A load and the circuit to the 60A load.

Cheers, Wayne
 
wwhitney said:
Conductors A are not a circuit by themselves, they are just a pair of parallel wires.
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They are a single set of circuit conductors, not separate circuit conductors. There is not two separate load currents on the conductors, there is one load current.

In your example the 60A ocpd is the final OCPD protecting that circuit, and yet you purport to have "feeder" conductors on the load side of that OCPD. Those "feeder" conductors do not meet the definition of Feeder, that is to say they are not between the source and the final branch circuit overcurrent device.
 
As far as the original post is concerned, I think we can agree there is little if any inherent danger in completing the install as described. It appears that this may be one of those situations where the only opinion on compliance that matters will be the local AHJ's.
 
I agree with Wayne here. So what exactly would be the code section that prohibits this? Give me an actual code section, Im not really sure you can throw out a sentance saying something about definitions when citing a code violation.....?
 
Feeder. All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device.
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Well, first of all, the definition of "feeder" already has some problems in its use of "the" final branch circuit overcurrent device. Most of what we recognize as feeder circuits will terminate in more than one branch circuit OCPD. Does that mean that they, by a strict reading of the definition, are not really feeders?

And if we change the language to substitute "a" for "the" the definition becomes logically better framed but at the same time leads toward recognition that in some cases there will in fact be multiple "final" OCPDs and branches and direct loads.

Branch Circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s).
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This does not have a problem with "the" since there will be only one source OCPD (possibly multi-pole or multiple fuses) for a given branch. And in the hybrid example we have been given the entire length of the conductors is in fact between the final OCPD protecting part of the circuit and the 60A outlet. The fact that there are other OCPDs branching off the conductors in question does not mean that the upstream conductors are feeder conductors. Unless you want to assert that the 60A load is in fact driven directly by a feeder without benefit of additional OCPD (which contradicts the definition of feeder, no?)

I think that we can all agree (fingers crossed) that the writers of the definitions assumed that there could not be any overlap and so failed to consider real life circuits which would cause problems with their definitions.

But based on what they ended up actually writing, my personal belief, based on logic and no assumption of intent, is that the circuit proposed is an example of conductors that are both feeder and branch.
 
GoldDigger said:
Well, first of all, the definition of "feeder" already has some problems in its use of "the" final branch circuit overcurrent device. Most of what we recognize as feeder circuits will terminate in more than one branch circuit OCPD....
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Really digging deep here, certainly much deeper that the code writers ever did, but you make a good point that could be used as evidence that a conductor can at least be multiple feeders at the same time. If one is of the school of thought that considers the panelboard bus a feeder, than it is serving as X feeders at the same time where X is the number of branch circuit breakers in the panelboard. So if a conductor can be technically multiple feeders, could it not be a feeder and a branch circuit in certain situations?
 
GoldDigger said:
The fact that there are other OCPDs branching off the conductors in question does not mean that the upstream conductors are feeder conductors. Unless you want to assert that the 60A load is in fact driven directly by a feeder without benefit of additional OCPD (which contradicts the definition of feeder, no?)
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it would meet the requirement of the 10 ft. feeder tap concept. In that concept it indicates a device without indicating the requirement of overcurrent protection for that portion of the feeder tap. You would unnecessarily be limiting that tap portion to 10 ft. when the circuit conductors are 60 amp.

(60 amp breaker)>>>>>feeder>>>>>(20 amp breaker)>>>>>Branch circuit>>>>>(20amp outlet)
................................................(feeder tap)>>>>>60 amp tap>>>>>(60 amp rec. outlet)
 
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david luchini said:
They are a single set of circuit conductors, not separate circuit conductors. There is not two separate load currents on the conductors, there is one load current.
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Actually, in my example there are two different possible load currents in Conductors A: the current when the 20A load is active, and the current when the 60A load is active [They are non-coincident, so those are the only possibilities.] Which is not surprising, because there are two different circuits.

david luchini said:
In your example the 60A ocpd is the final OCPD protecting that circuit, and yet you purport to have "feeder" conductors on the load side of that OCPD.
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You seem to be ignoring the 20A OCPD. Conductors A also run between the 60A OCPD and the 20A OCPD, so they are a feeder with respect to the 20A circuit.

Cheers, Wayne
 
wwhitney said:
Please tell me what part of post 35 you actually disagree with.
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Compliance of the proposed installation.

It treats an existing branch circuit as a feeder and adds another branch circuit without making the original branch circuit a feeder.
 
Smart $ said:
Compliance of the proposed installation.
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And what code section does it violate? Please provide a specific reference.

Smart $ said:
It treats an existing branch circuit as a feeder and adds another branch circuit without making the original branch circuit a feeder.
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I don't see how the configuration in the past matters for any of the applicable rules. Either the new configuration is code compliant, or it is not. We can ignore the past. [Unlike, say, the rules on adding an EGC to existing ungrounded circuits, or for allowing existing feeders without EGC to outbuildings, where the past clearly does matter to code compliance.]

Cheers, Wayne
 
wwhitney said:
And what code section does it violate? Please provide a specific reference.
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Here, I'll give you one not yet mentioned in this thread...
240.10 Supplementary Overcurrent Protection. Where
supplementary overcurrent protection is used for luminaires,
appliances, and other equipment or for internal circuits
and components of equipment, it shall not be used as
a substitute for required branch-circuit overcurrent devices or
in place of the required branch-circuit protection. Supplementary
overcurrent devices shall not be required to be readily
accessible.
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Is the 60 amp receptacle(s) in the OP "outlet(s)"?

Outlet.


A point on the wiring system at which current is taken to supply utilization equipment.
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Do they necessarily supply utilization equipment, or can they supply "feeders" to whatever the cord plugs into and then divide into individual branch circuits on this equipment?

Is a mobile home supplied via a 50 amp receptacle supplied by a feeder or a branch circuit? It definitely has additional branch circuits supplied from it's panelboard.
 
Smart $ said:
Here, I'll give you one not yet mentioned in this thread...240.10 Supplementary Overcurrent Protection.
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How does 240.10 apply to a feeder tap.
Unless there is an unwillingness to define a tap of a feeder as an extension of the feeder and the contention is a feeder tap must become a branch circuit.

240.2 Definitions. Tap Conductors. As used in this article, a tap conductor is defined as a conductor, other than a service conductor, that has overcurrent protection ahead of its point of supply that exceeds the value permitted for similar conductors that are protected as described elsewhere in 240.4.
 
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