3-pole single phase

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Suppose you have 3 circuits on one device?

3pdevices.jpg


OK, I know it's a long shot, but by the '08, a 3-pole could be used.
 
I found this ,..I did not look in the current white book but I'd place money it has not changed,..
http://wisconsin.iaei.org/annual_code_seminar.html
56. Can I install three phase overcurrent devices on a single-phase service installation and still be code compliant" Assuming the three-phase equipment comes with an approved neutral kit. Everything is the same except for the extra phase.

ANS: No, the UL General information Directory "White" book on page 14 under category DIVQ of the 2004 edition states that "3-pole circuit breakers are suitable for use only on 3-phase systems unless marked to indicate otherwise".
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selectelectric said:
if you read down just a bit though it says that multi-pole breakers can be used if the voltage is no more than 120v to ground
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So .......:-?
 
iwire said:
So that would make it OK with a 208Y/120 system
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I am not sure about that, these two statements seems to contradict each other.

3-pole circuit breakers are suitable for use only on 3-phase systems unless marked to indicate otherwise.
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Multi-pole common trip circuit breakers rated 120/240 V ac are suitable for use in a single-phase multi-wire circuit, with or without the neutral connected to the load, where the voltage to ground does not exceed 120 V.
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However I would think the first quote would take precedent since the second one may be referring to multipole as double pole ot 3 pole marked to indicate that it is suitable for sp operation.
 
:mad: AAAAARGH WHAT DOES IT ALL MEAN ,....sorry ,...but for crying out loud why is so damned hard to communicate an idea :-?
 
I am having a hard time not seeing this as an attempt to place a round peg into a square hole. Would a 3-pole breaker even be able to be inserted into a single phase panel, without the aid of a sledge hammer? :-?
 
charlie b said:
I am having a hard time not seeing this as an attempt to place a round peg into a square hole. Would a 3-pole breaker even be able to be inserted into a single phase panel, without the aid of a sledge hammer? :-?
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Assuming same brand and type usually yes without a problem.
 
I think the statements actually work together.

1: 3-phase only unless marked other wise.

2: Marked 120/240V multi-pole breaker circuits do not need a load neutral if L-G = 120V.
 
charlie b said:
I am having a hard time not seeing this as an attempt to place a round peg into a square hole. Would a 3-pole breaker even be able to be inserted into a single phase panel, without the aid of a sledge hammer? :-?
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Cutler-Hammer and Murray 1-2 & 3 pole breakers are exactly the same with the exception of the length of the rivets holding the pieces together. And the listing and labeling.
 
charlie b said:
I am having a hard time not seeing this as an attempt to place a round peg into a square hole. Would a 3-pole breaker even be able to be inserted into a single phase panel, without the aid of a sledge hammer? :-?
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Why wouldn't it? If, say, a Square D QO 1-pole breaker fits in both single- and three-phase panels, why wouldn't either 2- or 3-poles fit in both? Look at it from the manufacturer's point of view... would you want to produce two completely different breakers, one for single-phase and tool up the factory for the three-phase ones?

And again I will ask, why couldn't you use a 3-pole breaker to meet the requirements of 2008's 210.4(B)?
 
480sparky said:
Why wouldn't it? If, say, a Square D QO 1-pole breaker fits in both single- and three-phase panels, why wouldn't either 2- or 3-poles fit in both? Look at it from the manufacturer's point of view... would you want to produce two completely different breakers, one for single-phase and tool up the factory for the three-phase ones?

And again I will ask, why couldn't you use a 3-pole breaker to meet the requirements of 2008's 210.4(B)?
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What is the difference between a 3 phase and a 3 pole breaker? Beside what may or may not be written on the case, what would be a technical or physical difference?
 
480sparky said:
And again I will ask, why couldn't you use a 3-pole breaker to meet the requirements of 2008's 210.4(B)?
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That I can answer. Because a 3-pole breaker installed in a single phase panel will not create a multi-wire branch circuit. Look at the first sentence of the definition of MWBC. It requires there to be a voltage between the ungrounded conductors. A 3-pole breaker in a single phase panel will pick up Phase A, Phase B, and Phase A, and therefore there will not be voltage between two of the poles.
 
K8MHZ said:
What is the difference between a 3 phase and a 3 pole breaker? Beside what may or may not be written on the case, what would be a technical or physical difference?
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Three phase a characteristic of the electrical supply system. A three-pole breaker is simply a single component of the distribution system. Switches, for instance, are not rated for single- or three-phase installation. They are rated by # of poles. So a 3-pole switch can either be used to control a 3ph load, such as a motor, or three individual circuits.
 
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