NEC Definition

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mstrlucky74

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According to NEC definition I would say if you had conduitand wire from panel to a disconnect next to the motor that would be a feeder,not a branch circuit, as the disconnect is the final OCPD. Agree?

So if I'm running from a 1P-20a breaker to a FCU with a motor rated toggle, that's a feeder? The motor rated toggle is an OCPD, no? Or is the breaker only considered the OCPD? Why? TY
 
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mstrlucky74 said:
According to NEC definition I would say if you had conduitand wire from panel to a disconnect next to the motor that would be a feeder,not a branch circuit, as the disconnect is the final OCPD. Agree?

So if I'm running from a 1P-20a breaker to a FCU with a motor rated toggle, that's a feeder? The motor rated toggle is an OCPD, no? Or is the breaker only considered the OCPD? Why? TY
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Here are the NEC Definitions of Overcurrent protective device branch circuit and overcurrent protective device supplementary.

Overcurrent Protective Device, Branch-Circuit. A device capable
of providing protection for service, feeder, and branch
circuits and equipment over the full range of overcurrents
between its rated current and its interrupting rating. Such devices
are provided with interrupting ratings appropriate for the
intended use but no less than 5000 amperes.
Click to expand...
Overcurrent Protective Device, Supplementary. A device intended
to provide limited overcurrent protection for specific
applications and utilization equipment such as luminaires and
appliances. This limited protection is in addition to the protection
provided in the required branch circuit by the branchcircuit
overcurrent protective device.
Click to expand...

An motor rated toggle switch with overload protection would be a supplementary overcurrent device and not a branch circuit overcurrent device. Therefore the conductors from the Circuit breaker to the motor rated switch would be a branch circuit and not a feeder.

If the conductors from the breaker to the FCU terminated in a fused disconnect then it would be a feeder as the fused disconnect would contain Branch Circuit overcurrent protection.

Chris
 
raider1 said:
Here are the NEC Definitions of Overcurrent protective device branch circuit and overcurrent protective device supplementary.




An motor rated toggle switch with overload protection would be a supplementary overcurrent device and not a branch circuit overcurrent device. Therefore the conductors from the Circuit breaker to the motor rated switch would be a branch circuit and not a feeder.

If the conductors from the breaker to the FCU terminated in a fused disconnect then it would be a feeder as the fused disconnect would contain Branch Circuit overcurrent protection.

Chris
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I'm not seeing how these definitions would apply to a toggle switch with integral overload protection.
 
infinity said:
I'm not seeing how these definitions would apply to a toggle switch with integral overload protection.
Click to expand...
"Overload" was Chris' word, but I'm not sure that it is was the OP asked:

mstrlucky74 said:
So if I'm running from a 1P-20a breaker to a FCU with a motor rated toggle, that's a feeder? The motor rated toggle is an OCPD, no? Or is the breaker only considered the OCPD? Why? TY
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Z_-6s0fo5oy.JPG


To me, I read FCU as fused connection unit which could easily be what is shown in the image. Place a 15 Amp Type S Fusestat in it, and one has a 10,000 AIC rating. Now, I don't know if that is what Mstrlucky is describing. . . but it is a very common assembly, and an assembly that is the "final OCPD" that determines where the feeder ends and the branch circuit begins.
 
jumper said:
This subject gives me a headache, as long as it's wired correctly I don't care what you call it.

It's a branch circuit, no wait-it's a feeder.
Nope, I beg to differ-it's both.

Phooey, I say!:D
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Well.sir...what if the spec says all feeders to be xhhw? Might matter then.
 
mstrlucky74 said:
Well.sir...what if the spec says all feeders to be xhhw? Might matter then.
Click to expand...

My post was not directed at you by any means, it was a rant on the NEC.

Gads, the time we gotta spend figuring out the technical details boggle my brain at times.

Golddigger and I had a discussion on this type of install, my little brain twirled for a hour afterwards.

As far as what I would say it is. I pretty much agree with the headbanger (raider1).

PS. I should have used "someone" instead of "you" in my earlier post.
 
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mstrlucky74 said:

So if I'm running from a 1P-20a breaker to a FCU with a motor rated toggle, that's a feeder? The motor rated toggle is an OCPD, no? Or is the breaker only considered the OCPD? Why? TY
Click to expand...

Is mrlucky talking about one of these, a toggle switch (MMS) with integral overload protection (heater missing in photo) for the motor? This would not be an over-current device.

1H392_AS01
 
infinity said:
Is mrlucky talking about one of these, a toggle switch (MMS) with integral overload protection (heater missing in photo) for the motor? This would not be an over-current device.

1H392_AS01
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I agree with you about this form of a switch. And, in this photo, the circuit conductors serving the Line side connections would be Branch Circuit conductors.
 
jumper said:
Okay, how about this.

20A circuit fed from a cb in panel to a SSU switch, the one you posted, with a 20A fuse?
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The SSU I'm familiar with is the Bussman Edison base plug fuse box cover. Clicking on that link opens a PDF data page that says the SSU is rated only for 15 Amps.

For your question, if you'll allow the circuit breaker in the panel to be 15 Amp, and the plug fuse in the SSU to be a 15 A Type S Fusestat and adapter, then:

jumper said:
Between cb and switch is...?
Click to expand...
The Feeder.

jumper said:
Between switch and equipment is....?
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The Branch Circuit if there is a field assembled wiring method (like NM, MC or EMT, etc.) between the SSU box and the equipment conductors.

Note, I equivocate here because I've seen all to many residential forced air furnaces supplied through a SSU, where the SSU is mounted directly over the furnace supply 1/2" K.O. and the internal furnace wiring is pulled through into the SSU and directly terminated on the SSU with no additional wire added. In such cases, I am of the opinion that there is no branch circuit.
 
al hildenbrand said:
The SSU I'm familiar with is the Bussman Edison base plug fuse box cover. Clicking on that link opens a PDF data page that says the SSU is rated only for 15 Amps.

For your question, if you'll allow the circuit breaker in the panel to be 15 Amp, and the plug fuse in the SSU to be a 15 A Type S Fusestat and adapter, then:


The Feeder.


The Branch Circuit if there is a field assembled wiring method (like NM, MC or EMT, etc.) between the SSU box and the equipment conductors.

Note, I equivocate here because I've seen all to many residential forced air furnaces supplied through a SSU, where the SSU is mounted directly over the furnace supply 1/2" K.O. and the internal furnace wiring is pulled through into the SSU and directly terminated on the SSU with no additional wire added. In such cases, I am of the opinion that there is no branch circuit.
Click to expand...

Okay, I gotta a few more thoughts on this subject, but I do not want to theadjack here. I am gonna start a new thread. No time today, I will post it tomorrow.
 
mstrlucky74 said:
According to NEC definition I would say if you had conduitand wire from panel to a disconnect next to the motor that would be a feeder,not a branch circuit, as the disconnect is the final OCPD. Agree?

So if I'm running from a 1P-20a breaker to a FCU with a motor rated toggle, that's a feeder? The motor rated toggle is an OCPD, no? Or is the breaker only considered the OCPD? Why? TY
Click to expand...

Art 430 would call that a motor branch circuit. Please refer to figure 430.1
 
tom baker said:
Art 430 would call that a motor branch circuit. Please refer to figure 430.1
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I agree. Doesn't matter which switch type was used (of the two that have been posted). Each switch is (or can be) considered a motor controller, plus it contains overload protection. The SSU switch is not listed as a branch circuit device and can only be a supplemental device, though it can provide short circuit and ground fault protection as well as motor overload protection - if appropriate fuse is selected. Both switch types are suitable as the local motor/appliance disconnecting means.
 
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