3-pole toggle disconnect

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JoeNorm

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I am running into a few situations where I need to provide disconnecting means for 3, 120v 20a circuits.

I found a 30a rated 3-pole toggle motor switch(looks like it's small enough to fit in a Bell box) I thought would do the trick. Any problem with this? My main clarification was whether each pole was in fact rated at 30 amp? And yes, I will be pulling a separate neutral for each circuit.

thanks
 
Used quite frequently on rooftop exhaust fans In a handy box, but really tight. You would most likely be really over the box fill on the bell box, deep 1900 with an rs cover would probably be needed, and it would probably be close with 9 #10, #10 ground, and the device deduction. (If you pull the neutrals straight thru)
 
The OP was about the Leviton in the above picture. Maybe it needs to go into a 2gang Bell box, that would be fine too. I'd be using it with #12 AWG wire
 
You have to look close as most equipment of that type is only listed for the disconnection of a single circuit. In your case, with three 120 volt circuits, if you are on a three phase system, you could make it a single multiwire circuit and be in compliance with the listing.
 
don_resqcapt19 said:
You have to look close as most equipment of that type is only listed for the disconnection of a single circuit. In your case, with three 120 volt circuits, if you are on a three phase system, you could make it a single multiwire circuit and be in compliance with the listing.
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I'm curious-- given your last sentence, what possible technical justification could there be for that listing distinction? I mean, if it can disconnect 3 separate legs of a 3 phase system when those legs share a common neutral, why can't it do it when there isn't a nearby common neutral? And if can disconnect 3 legs all at pairwise nonzero voltages, why can't it do the same when some of the pairwise voltages are 0, again whether or not there is a nearby common neutral?

I can see a requirement that all the conductors be from a common voltage system, so that they have a well defined voltage between them.

Cheers, Wayne
 
I can see it being required that the three circuits are supplied through a 3p (or tied) breaker(s) since they would be supplying a single device (yoke).
 
wwhitney said:
I'm curious-- given your last sentence, what possible technical justification could there be for that listing distinction? I mean, if it can disconnect 3 separate legs of a 3 phase system when those legs share a common neutral, why can't it do it when there isn't a nearby common neutral? And if can disconnect 3 legs all at pairwise nonzero voltages, why can't it do the same when some of the pairwise voltages are 0, again whether or not there is a nearby common neutral?

I can see a requirement that all the conductors be from a common voltage system, so that they have a well defined voltage between them.

Cheers, Wayne
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There is no reason a rule has to have a technical substantiation :) ...just a rule.
From the UL Guide Information for snap switches
Multi-pole, general-use snap switches have not been investigated for more than single-circuit operation unless marked "2-circuit" or "3-circuit."
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404.8 (C) Multipole Snap Switches.
A multipole, general-use snap switch shall not be permitted to be fed from more than a single circuit unless it is listed and marked as a two-circuit or three-circuit switch.
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The scope of UL 20 for general use snap switches includes most type of switches that are installed in boxes, but would not include a manual motor starter.
 
Should I infer from the use of the bare word "circuit" in 404.8(C), rather than the defined term "branch circuit," that it is not restricting snap switches to a single branch circuit? : - ) Broadly speaking, two branch circuits on a single feeder could be seen as single circuit.

Cheers, Wayne
 
wwhitney said:
Should I infer from the use of the bare word "circuit" in 404.8(C), rather than the defined term "branch circuit," that it is not restricting snap switches to a single branch circuit? : - ) Broadly speaking, two branch circuits on a single feeder could be seen as single circuit.

Cheers, Wayne
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How???
 
don_resqcapt19 said:
How???
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The only thing making a branch circuit a branch circuit is the location of the final OCPD. So if the term circuit is more general and ignores the location of OCPD, everything supplied by a given transformer or other source is one big circuit.

Pretty sure they mean branch circuit, just frustrating when the NEC has an applicable defined term and then sections don't use it properly.

Cheers, Wayne
 
wwhitney said:
The only thing making a branch circuit a branch circuit is the location of the final OCPD. So if the term circuit is more general and ignores the location of OCPD, everything supplied by a given transformer or other source is one big circuit.

Pretty sure they mean branch circuit, just frustrating when the NEC has an applicable defined term and then sections don't use it properly.

Cheers, Wayne
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not buying that one :D
 
Also be cognizant of whether this needs to be used for Lock-Out / Tag-Out purposes. If you buy them as a "Manual Motor Starter", they can have a hasp loop to accept a padlock.
LEVMFC_MP_N1302-DS.jpg
 
Thanks all. This is residential application for septic systems. Often there are two motors and controls fed by three circuits. Trying to find a clean and simple way to shutdown the three circuits. Lockout not an issue here.
 
don_resqcapt19 said:
not buying that one :D
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For the sake of discussion, consider the multi-line diagram below of a 3 phase system.

How many circuits is it? I could call it one circuit starting at A, or 3 circuits starting at B, or just look at the red leg 2-wire circuit from A to its load, etc. The above all applies regardless of location of OCPD, circuit is a general term.

How many branch circuits is it? That depends on OCPD location. If A has OCPD, and B is just a junction box, it can be considered 1 multiwire branch circuit. Or it can be considered 3 branch circuits, per the intentional ambiguity the NEC allows.

While if A and B both have OCPD for the circuit(s), then A to B is 1 feeder, and B supplies 3 branch circuits.

Cheers, Wayne

circuit.jpg
 
don_resqcapt19 said:
You have to look close as most equipment of that type is only listed for the disconnection of a single circuit.
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FWIW, UL 20 has a weak implication that a 3 pole switch should be listed for 3 circuits, but I have not confirmed that by checking the instructions of any product. I say that because the latest revision added two definitions and some according sections on marking:

"Single pole, 3-way, 4-way or 2 pole switches" which the definition says should be "supplied by a single branch circuit."
"Two or Three Circuit Switches" which the definition says are intended to be "supplied by multiple single phase branch circuits."

So the weak implication is that the only defined term referencing 3 pole switches is the "Three Circuit Switch." But that's not very strong.

Anyway what the OP wants is a switch that meet the UL 20 definition of "three circuit switch."

Cheers, Wayne
 
wwhitney said:
For the sake of discussion, consider the multi-line diagram below of a 3 phase system.

How many circuits is it? I could call it one circuit starting at A, or 3 circuits starting at B, or just look at the red leg 2-wire circuit from A to its load, etc. The above all applies regardless of location of OCPD, circuit is a general term.

How many branch circuits is it? That depends on OCPD location. If A has OCPD, and B is just a junction box, it can be considered 1 multiwire branch circuit. Or it can be considered 3 branch circuits, per the intentional ambiguity the NEC allows.

While if A and B both have OCPD for the circuit(s), then A to B is 1 feeder, and B supplies 3 branch circuits.

Cheers, Wayne

View attachment 2564780
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A single OCPD only supplies a single circuit.
We are done here as we will NEVER agree on this
 
don_resqcapt19 said:
A single OCPD only supplies a single circuit.
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A multiple pole OCPD in a system with a grounded conductor could certainly supply multiple 2-wire branch circuits. So do you want to collectively call those a single circuit?

Anyway, what my point was that the bare term "circuit" is not the same as the term "branch circuit." So I am wondering if 404.8(C) is being imprecise when it says "circuit," and I should submit a PI to change it to "branch circuit." Since the UL 20 definitions I paraphrased earlier do use the term "branch circuit."

Or perhaps 404.8(C) is trying to make a broader or narrow statement intentionally by not using the term "branch circuit."

Cheers, Wayne
 
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