Half circuits don't work

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Billy_Bob said:
Sometimes you have a 240V tie-bar breaker which is really two separate breakers connected together via the tie bar (and the tie bar has a lot of play in it). One breaker will trip, but the other will remain on. So you get one leg dead and the other leg with power remaining.
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I'll be gentle, since you're new here.

A 2-pole breaker will trip both poles even if you pry the handle-tie off. The handle tie is there srtictly to assure simultaneous manual operation.

There is a mechanical connection between the breaker cases that connects the mechanisms. That's what "common internal trip" means.

Oh, that goees for 3-pole breakers, too. And, welcome to the forum.
 
LarryFine said:
A 2-pole breaker will trip both poles even if you pry the handle-tie off. The handle tie is there srtictly to assure simultaneous manual operation...
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Well that is how they *should* work...

But I seem to recall a 2 pole breaker somewhere where just one leg had tripped. That was a long time ago though!
 
LarryFine said:
I'll be gentle, since you're new here.

A 2-pole breaker will trip both poles even if you pry the handle-tie off. The handle tie is there srtictly to assure simultaneous manual operation.

There is a mechanical connection between the breaker cases that connects the mechanisms. That's what "common internal trip" means.

Oh, that goees for 3-pole breakers, too. And, welcome to the forum.
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I am sure you meant to exclude Pushmatic breakers. They must date proir to "common internal trip". Simultaneous manual operation was tricky on occassion.
 
Billy_Bob said:
Well that is how they *should* work...

But I seem to recall a 2 pole breaker somewhere where just one leg had tripped. That was a long time ago though!
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Could have been some well meaning hack...:grin: Seriously, I don't know how it would affect it, but someone could have turned one side off.

Either that, or you've lost a phase, or have a loose / corroded / bad connection somewhere.
 
Disclaimer: The following statement refers to modern equipment.

LarryFine said:
A 2-pole breaker will trip both poles even if you pry the handle-tie off. The handle tie is there srtictly to assure simultaneous manual operation.
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DanZ said:
So, if it was some Git-R-Done type or HD Dude, who decided you could put two 20A 120V Breakers together to make a 40A 240V Breaker, it would trip both?:rolleyes:
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It might, but it would make them look like a 20a, 240v breaker. A 40a, 240v breaker would require two 40a, 120v breakers. Even then, the handles can not be relied upon to open both breakers when one trips.

It may well work, but it isn't compliant for a circuit that supplies line-to-line loads. Handle-ties are only compliant for MWBC's with only line-to-neutral loads. Line-to-line loads require an internal common trip.
 
LarryFine said:
It might, but it would make them look like a 20a, 240v breaker. A 40a, 240v breaker would require two 40a, 120v breakers. Even then, the handles can not be relied upon to open both breakers when one trips.

It may well work, but it isn't compliant for a circuit that supplies line-to-line loads. Handle-ties are only compliant for MWBC's with only line-to-neutral loads. Line-to-line loads require an internal common trip.
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The 20A to 40A was typed with my tongue firmly in my cheek. I believe there is another post somewhere where a guy from HD told someone to buy two 20's to make 40...it may have been two 30s to make 50.

I do know the handles can't be relied upon, and it's not compliant, but who knows who had their hands in the panel before.

One of the oldest sayings I have, that I'm very fond of is "Dummy check everything, twice."
 
LarryFine said:
I'll be gentle, since you're new here.

A 2-pole breaker will trip both poles even if you pry the handle-tie off. The handle tie is there srtictly to assure simultaneous manual operation.

There is a mechanical connection between the breaker cases that connects the mechanisms. That's what "common internal trip" means.

Oh, that goees for 3-pole breakers, too. And, welcome to the forum.
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what if you installed 2 single pole breakers and handle tied them together, but the handle tie was loose then perhaps one trips and the other doesn't..........I'll admit, I doubt that's what is the problem here though.
 
steelersman said:
what if you installed 2 single pole breakers and handle tied them together, but the handle tie was loose then perhaps one trips and the other doesn't..........I'll admit, I doubt that's what is the problem here though.
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The ite dp twin breakers would often do just that with the outer pair. You could flip one but not the other. That was years ago I assume they changed that.
 
electricalperson said:
i think he deleted his profile or something. i dont know why he left i liked him he was nice. on that note i wish pierre c belarge would come back
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Pierre was lurking at 2:40 pm today.
 
electricalperson said:
i think he deleted his profile or something. i dont know why he left i liked him he was nice. on that note i wish pierre c belarge would come back
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That was my thought, but he's posted a week ago or so and had that, and here he is today. Maybe he's in stealth mode! :grin:

I'm beginning to wonder what happened to Pierre C Belarge. Pierre, if you're out there, say hi! There are people here who miss you.;)
 
iwire said:
Glad were not trying to over think this problem.
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Yeah,
Just tell them to pay the other half of their electric bill :grin:
 
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