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Quote:
Originally Posted by 480sparky

So you've never hooked up a 240 air conditioner compressor, or electric water heater?
Those are not MWBCs.



:whistling2:


You are correct. Those are motor branch circuits.
A water heater is not a motor branch circuit.

You're statement that 2 & 3-pole breakers were only for MWBC is not correct and that is what everyone is on you about.
I'm sure (hope) you know you're statement as written is not correct.
But that is what you wrote and it needed correcting.
 

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Yes, a 208V single phase circuit from a 120/208V 3 Phase service. A 2P breaker in a 3 Phase panel...not a MWBC.

I brought up a different example to help you figure this out.
Well you are mistaken. 2pole and 3pole breakers can and do exist as multiwire branch circuits. Think of a cubicle.

Your 208 "single phase" example is completely wrong and not even possible. As I said earlier, you need two of the three phases to get 208.
You are new here and I'm trying to help you out in a kind way. But you're not making it easy!:jester: I'm thinking you must be a transplant to the "South", because you're making us look bad!:laughing:

This whole discussion started with your statement that all 2/3-pole beakers were for MWBC. Which I (and others) told you was not correct.

No one has said that 2/3-poles can't be a MWBC, only that that is not the only (or primary) use for them.

Anytime you only use two phases you are using single phase.
Example: 240V single phase (L1-L2) load from a 120/240V 3ph system = single phase load

208V single phase (L1-L-2) resistive heater from a 208/120V system = single phase load.

So if someone asked you to hook up their 208/240V single phase water heater up, how would you wire it? Maybe a 2-pole breaker? And that would not be a MWBC.
 

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You and your buddy like to imagine I said 2 phase, but it never happen.


I did say this ^^
This is correct because...
In a 240Y/120 wye 3-phase two of the three phases are required to get 208v. Get with it man. It's not rocket science and please, please read something before you post it.
You're talking about two different voltages/systems. You won't get 208V between two of the legs/phases on a 240/120V system. If it is a delta with a high leg you will get 208V phase to neutral from the high leg.

Only time you get 208V between phases/legs is on a 208/120V system.
If you have a wye you're not going to have a 240/120V system.
 
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