Feeder or Branch?

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Farklesnarf

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If a motor is fed from a breaker, originating from a main service panel, such as an All-in-One on a residence, is that circuit a Branch for Feeder?
 
Article 100 has the answer:

Branch Circuit, Individual.
A branch circuit that supplies only one utilization equipment.

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.
 
What is an "all in one"- does this mean that the breaker in the panel is also the disconnect for the motor? If so then it is a branch circuit
 
It depends on what the load end of the conductors land in first.

If the load, then branch circuit; if a sub-panel, breaker, or fused switch, then feeder.
 
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When I install service for irrigation wells, the pump panel has a disconnect with overcurrent protection and in those situations it fulfills both the service disconnecting means as well as the branch circuit OCPD for that pump motor. It can be this way for any situation that has a single load being served.


Some those limited load applications might have more than the one load, but you can have up to six service disconnecting means at the site as well. Each one might only be serving a single load. My irrigation services often has at least two service disconnects, one for the well, one for the center pivot machine. Load side of both is considered to be a branch circuit.
 
Thanks guys! I'm understanding that the circuit from the breaker to the motor disco, by definition is a feeder, and the wiring from the disco to the peckerhead is a branch circuit.
 
Thanks guys! I'm understanding that the circuit from the breaker to the motor disco, by definition is a feeder, and the wiring from the disco to the peckerhead is a branch circuit.
As long as the motor disco contains OCPD.

Also, for fun, consider the following situation: Service panel, one breaker in it feeds two motor, one of which has a starter with integral OCPD, the other is thermally protected and does not need a starter or overload.
The line leaving the main panel is simultaneously a feeder and a branch circuit, and has to follow the applicable rules for both (whichever is more restrictive for any given property.)
You will find arguments here about whether it is "really" a feeder or a branch circuit. Some will even assert that since "it is impossible for one circuit to be both a feeder and a branch", that configuration must not be legal.
 
Thanks guys! I'm understanding that the circuit from the breaker to the motor disco, by definition is a feeder, and the wiring from the disco to the peckerhead is a branch circuit.

Exactly but as golddigger stated there would have to be a overcurrent protective device in the disconnect. I wrote a proposal to make an exception in this situation. I proposed that if there was one piece of equipment fed from a panel to a disconnect with overcurrent protective device then the entire run would be a branch circuit.

I had a cmp member agree with me but my proposal did not make it. If there is overcurrent protective device in the disconnect then one part is a feeder and the other a branch circuit but if there is no overcurrent protective device then the entire run is a branch circuit... doesn't make sense in this situation
 
I had a cmp member agree with me but my proposal did not make it. If there is overcurrent protective device in the disconnect then one part is a feeder and the other a branch circuit but if there is no overcurrent protective device then the entire run is a branch circuit... doesn't make sense in this situation
I agree. IMO the fuses in the disconnect are supplementary protection making it a branch circuit.
 
I agree. IMO the fuses in the disconnect are supplementary protection making it a branch circuit.
If there is say a reduction in conductor size and similar reduction in overcurrent device then it possibly is a feeder then branch circuit.

If you have same size conductor both sides of disconnect I'd say there is lesser chance it is feeder then branch circuit.

You could have say a 25 amp circuit breaker and then fused disconnect with only 20 amp fuses - simply because you can typically use lesser rating on time delay fuses than you can on a mag trip breaker for same motor. In that situation I still say the entire run is a branch circuit and the fuses are nothing more than a supplemental device.
 
I agree. IMO the fuses in the disconnect are supplementary protection making it a branch circuit.
Seems to me there's a simple test for when that interpretation is applicable. Namely, if you deleted those fuses, would you still have an NEC-compliant installation, as far as OCPD and conductor sizing? If so, then you can call those fuses supplementary. If not, they are clearly not supplementary.

Cheers, Wayne
 
Seems to me there's a simple test for when that interpretation is applicable. Namely, if you deleted those fuses, would you still have an NEC-compliant installation, as far as OCPD and conductor sizing? If so, then you can call those fuses supplementary. If not, they are clearly not supplementary.

Cheers, Wayne
Excellent way to approach this.
 
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