Handle ties on breakers

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Rock86

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They would be common trip, which is not the same as mechanically connected in terms of manually opening and resetting after trip.
Curiosity asks: Once the common trip is triggered, do you have to reset (off-on) the handle on both sides to get even one pole to close?
I was referring to the construction of the breakers... two individual breakers being side by side mechanically connected with a handle tie for common trip. if you removed the handle tie, and connected single branch circuits to each, then they would act as individual breakers. but the OP is discussing QO style breakers which are 2 pole breakers with one handle. you can't separate that into two individual circuits. I regret making the case.
 

Dennis Alwon

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I was referring to the construction of the breakers... two individual breakers being side by side mechanically connected with a handle tie for common trip. if you removed the handle tie, and connected single branch circuits to each, then they would act as individual breakers. but the OP is discussing QO style breakers which are 2 pole breakers with one handle. you can't separate that into two individual circuits. I regret making the case.

You don't have to separate the dp breaker to get 2 individual circuits. Handle ties do not make the breakers a common trip either.

A dp breaker can handle one 120v circuit, 2- 120v circuits, a multiwire branch circuit, or a 240V circuit-- assuming 120/240

A dp breaker is a common trip device
 

jap

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I was referring to the construction of the breakers... two individual breakers being side by side mechanically connected with a handle tie for common trip. if you removed the handle tie, and connected single branch circuits to each, then they would act as individual breakers. but the OP is discussing QO style breakers which are 2 pole breakers with one handle. you can't separate that into two individual circuits. I regret making the case.

I understand what you are saying.

But,

Even though the the (2) Separate breakers are "joined" together physically they do not act as "Individual" breakers.

On a 2p common trip even without the handle tie, if one side trips, both sides trip, but, one side cannot be reset without the other side being reset.

Both sides have to be reset at that same time as if the handle tie was still in place.

Therefore they actually do not function as (2) individual breakers.

If they were actually (2) individual breakers simply "joined" together, and, you removed the handle tie, one would not trip when the other one did, and, one would not be dependent on the other to reset like an actual 2p common trip breaker is.

JAP>
 

Little Bill

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If you are referring to the tandem breaker no reason to, should never be used for MWBC, overloads the neutral.


100% agree. No different than using a full size breakers and skipping a space with a MWBC. What would the inspector say to that installation? If he has any knowledge he would say no to that, he was not thinking, inspector speaking off the cuff and you can get poor advice. Would be interested in the inspectors reply if you call him to the question about a MWBC being on 2 breakers that skip a space putting them on the same buss .
With two circuits on the same bus, it isn't a MWBC. They have to have a voltage potential between them. All you have is a circuit(s) possibly overloading the neutral.
 

jap

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If you are referring to the tandem breaker no reason to, should never be used for MWBC, overloads the neutral.


100% agree. No different than using a full size breakers and skipping a space with a MWBC. What would the inspector say to that installation? If he has any knowledge he would say no to that, he was not thinking, inspector speaking off the cuff and you can get poor advice. Would be interested in the inspectors reply if you call him to the question about a MWBC being on 2 breakers that skip a space putting them on the same buss .


Careful Fred,,,, not all services are 120/240v single phase.

In a 3ph 4w scenario what you just described would be considered a MWBC because they would not end up on the same bus. :)

JAP>
 

nickelec

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US
I was taking about tandems yes , I had no patience to sit there and argue/educate this guy so I just did it and took them off when he left

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Fred B

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Upstate, NY
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Electrician
Careful Fred,,,, not all services are 120/240v single phase.

In a 3ph 4w scenario what you just described would be considered a MWBC because they would not end up on the same bus. :)

JAP>
Thank you, True 3ph would be breaker on the third skipping 2 spaces. Also need to be careful because that could land it on the wild leg if present. So probably better stated as simply skipping space to land on same bus.
With two circuits on the same bus, it isn't a MWBC. They have to have a voltage potential between them. All you have is a circuit(s) possibly overloading the neutral.
I'm not saying it's correct, but I have seen someone wire what was supposed to be a MWBC in just the way I described, and neutral was very burnt. I was just replying to @nickelec and @LarryFine comments relating use of tandem for a MWBC and I responded it is no different than scenario I laid out with a (corrected by @jap 120/240 1ph) skipped breaker spacing and it landing on same bus. Care further would be needed when using the double tandem made by Siemens, it let's you have 2 MWBC in the space of just 2 breakers. I've seen them in 20/20, 15/15, 15/20, 15/30 and 20/30 and with add on handle ties for outer handles.
1627081271926.png
 

Fred B

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Upstate, NY
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Electrician
Note that only the inner poles have internal common trip.
Yes have used for hot water heater and 2 - 1p circuits. I've also have used ones with no common trip and using with or without handle ties to make room to add an AFCI circuit to a full panel.
 

GoldDigger

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Placerville, CA, USA
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Home Depot thinks Siemens 30/30 quad breaker the outer poles are also common trip, don't know if bad translation. Or something inside to link outer poles?
Some manufacturers offer the same breaker and handle configuration with no common trip, inside only common trip, and both common trip under slightly different part numbers. When in doubt go by the label on the breaker itself.
HD does a pretty poor job on transferring manufacturer specs to their site.
I came across a ladder online that was rated for 300 pounds and the spec said 375. Someone called their attention to it online a year ago and the HD web assistance guy wrote that the manufacturer's spec was wrong and the HD spec was right. Still not fixed a year later.
 
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