Tap rule question

[don_resqcapt19]

I agree with David.
Tapping a branch circuit conductor in no way changes that conductor to a feeder conductor.

 

[rlundsrud]

I think we can all agree to disagree with those that disagree with anyone who agrees. I hope that this argument isn't going to disagree with anyone who previously agreed, but I agree that I am disagreeable with respect to the aforementioned agreement.

 

[david]

I agree with David.
Tapping a branch circuit conductor in no way changes that conductor to a feeder conductor.

This seems to be stumbling over definitions,

Are we to understand that if someone takes a 90 amp circuit from a 90 amp breaker through a facility to a J box that was intended for a branch circuit. Changes there mind ,but because this was initially used or being used as a branch circuit, they cannot reconfigure the circuit into a feeder.

I cannot see why if at the end result the circuit could be defined as a feeder it must forever be a branch circuit.

As an inspector and you do not indicate that the circuit originally started out as a branch circuit

I agree with David.

would it be cheating to change the above to

QUOTE=don_resqcapt19;1682691]I agree with david.[/QUOTE

 

[GoldDigger]

would it be cheating to change the above to

QUOTE=don_resqcapt19;1682691]I agree with david.[/QUOTE

Not if you do it correctly. Just add the "FIFY" (Fixed It For You) tag line.

Put back the leading "[" and trailing "]" and nobody will notice.

 

[david luchini]

I cannot see why if at the end result the circuit could be defined as a feeder it must forever be a branch circuit.

I don't see where anyone has suggested that that a branch circuit must forever be a branch circuit.

 

[wwhitney]

I don't see where anyone has suggested that that a branch circuit must forever be a branch circuit.

OK, so you agree that in the OP the addition of downstream OCPD changes it into a feeder?

Cheers, Wayne

 

[Smart $]

Any chance you guys can go a few more rounds on the matter... :angel:


David believes circuit conductors cannot be both feeder and branch circuit conductors concurrently by NEC definition. Technically, he is correct.


And I agree... but only technically. :slaphead:

 

[wwhitney]

David believes circuit conductors cannot be both feeder and branch circuit conductors concurrently by NEC definition. Technically, he is correct.

Sincerely, can you explain that? How do the definitions not overlap? As I've pointed out, you can wire OCPD and outlets in a pattern where some of the conductors meet both definitions. Does some other code section I've missed prohibit this?

Cheers, Wayne

 

[don_resqcapt19]

Sincerely, can you explain that? How do the definitions not overlap? As I've pointed out, you can wire OCPD and outlets in a pattern where some of the conductors meet both definitions. Does some other code section I've missed prohibit this?

Cheers, Wayne

I don't see how any conductor can be in compliance with both definitions.

 

[GoldDigger]

I don't see how any conductor can be in compliance with both definitions.

Are you basing that on the idea that a circuit with one directly wired outlet and one connection to an OCPD with downstream loads is somehow prohibited?
If that configuration is in fact allowed (and I think it is) then the wires from the source breaker (which is both a feeder and a branch breaker!) to the point where the paths to outlet and OCPD diverge are both branch wires and feeder wires.
If the configuration is allowed, then the load calculation for the circuit could be a little dicey, since the rules for branch circuits and the rules for feeders differ slightly. I guess you figure the load both ways and use the larger wire size.

 

[david luchini]

OK, so you agree that in the OP the addition of downstream OCPD changes it into a feeder?

Cheers, Wayne

See post #7. He could first turn the branch circuit into a feeder and then apply the feeder tap rules to the the new feeder. He cannot apply the feeder tap rules to the branch circuit.

 

[Smart $]

Sincerely, can you explain that? How do the definitions not overlap? As I've pointed out, you can wire OCPD and outlets in a pattern where some of the conductors meet both definitions. Does some other code section I've missed prohibit this?

As Don notes, no single conductor can be in compliance with both definitions... concurrently. I leave it to you to determine the rationale.

 

[don_resqcapt19]

Are you basing that on the idea that a circuit with one directly wired outlet and one connection to an OCPD with downstream loads is somehow prohibited?
If that configuration is in fact allowed (and I think it is) then the wires from the source breaker (which is both a feeder and a branch breaker!) to the point where the paths to outlet and OCPD diverge are both branch wires and feeder wires.
If the configuration is allowed, then the load calculation for the circuit could be a little dicey, since the rules for branch circuits and the rules for feeders differ slightly. I guess you figure the load both ways and use the larger wire size.

I guess I am saying you can't do that as there are no rules that cover how you would install that circuit. That is based on the fact that using the NEC definitions there is no possible way that a circuit conductor can be both a branch circuit conductor and a feeder conductor at the same time.

 

[wwhitney]

I guess I am saying you can't do that as there are no rules that cover how you would install that circuit.

Not a problem--if some conductors are both a feeder and branch circuit conductors, then they have to comply with the rules for both. Just like one conductor could be both an EGC and a GEC, before that was explicitly prohibited.

Cheers, Wayne

 

[wwhitney]

As Don notes, no single conductor can be in compliance with both definitions... concurrently.

OK, what about the wiring configuration jap proposed in post 19?

60A OCPD
|
60A conductors A
|
J-Box -- 60A conductors B -- 20A OCPD -- 20A conductors C -- 20A load
|
60A conductors D
|
60A load

There are no taps here. To obviate any load calculation issues, let's say that the 20A and 60A loads are non-coincident.

Those 60A conductors A meet both NEC definitions for a feeder and a branch circuit:

Branch Circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s).

Conductors A are between the 60A OCPD and the 60A load, the 60A OCPD is the final OCPD for the outlet at the 60A load, so Conductors A are branch circuit conductors.

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.

Conductors A are between the 60A OCPD and the 20A OCPD, and the 20A OCPD is the final OCPD for the 20A load. So Conductors A are between the power supply source and the final branch-circuit OCPD, and Conductors A are a feeder.

Please explain how this installation is not NEC-compliant, or how I've misread the definitions above.

Thanks,
Wayne

P.S. As to the OP, conductors B above are definitely a feeder. So regardless of what you call conductors A, you can apply the feeder tap rules to conductors B, and downsize them to 20A conductors if you comply with the feeder tap rules.

 

[Smart $]

...
60A OCPD
|
60A conductors A
|
J-Box -- 60A conductors B -- 20A OCPD -- 20A conductors C -- 20A load
|
60A conductors D
|
60A load

...

Note 60A OCPD protects conductors to 60A load at bottom as branch circuit conductors. They cannot be feeder circuit conductors at the same time.

 

[wwhitney]

Note 60A OCPD protects conductors to 60A load at bottom as branch circuit conductors. They cannot be feeder circuit conductors at the same time.

That's a common idea. But where does the NEC say that? The definitions don't.

Cheers, Wayne

 

[don_resqcapt19]

That's a common idea. But where does the NEC say that? The definitions don't.

Cheers, Wayne

They very clearly say that to me

 

[Smart $]

That's a common idea. But where does the NEC say that? The definitions don't.

Cheers, Wayne

The definitions most certainly say that.

Branch Circuit. The circuit conductors between the final
overcurrent device protecting the circuit and the outlet(s).

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.

 

[wwhitney]

60A OCPD
|
60A conductors A
|
J-Box -- 60A conductors B -- 20A OCPD -- 20A conductors C -- 20A load
|
60A conductors D
|
60A load

Conductors A run between the two OCPD in red. So they meet the definition of a feeder.

And as Smart$ showed, they meet the definition of a branch circuit (edit: with respect to the 60A load).

Nothing in the definitions says they are mutually exclusive.

Cheers, Wayne