2 pole common Trip or Handle tie

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brother

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I dont have my code book in front of me at the moment. it seem to have slip my mind on this issue. We have a 208v receptacle (2 hots 1 ground 20 amp) that is being installed from an existing panel. It was my understanding that we had to have a 2 pole 'common trip' breaker, instead of using 2 single pole breakers with a handle tie. I Know there are exceptions for 120/240 breakers but cant remember them at the moment. And as far as I know one cannot use 2 single breakers with handle ties for 277/480 receptacles, equipment.

Am I right in this, or is it ok to use the 2 single pole breakers (208 volt) with a handle tie in this application. We are on the 2017 nec.
 
Since there is no neutral involved you can use two single poles with a handle tie or a 2 pole CB.
 
infinity said:
Since there is no neutral involved you can use two single poles with a handle tie or a 2 pole CB.
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Ok. Thanks. So if understand this correctly, if this receptacle was a 4 wire, (2 hots and neutral and ground) then a common trip would be required? But without a neutral , line to line 208 then a handle tie is ok?

Seems odd to me since the purpose of it is to clear a fault and open the circuit breaker, but I don't have my code book at present. Thanks for the quick reply.
 
brother said:
Ok. Thanks. So if understand this correctly, if this receptacle was a 4 wire, (2 hots and neutral and ground) then a common trip would be required? But without a neutral , line to line 208 then a handle tie is ok?

Seems odd to me since the purpose of it is to clear a fault and open the circuit breaker, but I don't have my code book at present. Thanks for the quick reply.
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Since there is no neutral to the load, the load must be connected line to line. That means that opening either line conductor by itself will interrupt current to that load (in case of an internal short, for example). If the short is to ground, then it is likely to result in excess current in both lines and both breakers will open.
In the specific case of a motor with no other single-phasing detection and protection, it would be prudent to use a common trip breaker only.
 
Simultaneous operation

Simultaneous operation

My interpretation is if one pole trips or is turned off the other pole(s) must also do the same simultaneously. Thereby ensuring all power to the unit has been interupted. Another point concerning breaker ties is does the tie being used have to be made by the same OEM that made the breaker? I would assume so seeing the breakers in a panel must match the panel manufacturers specifications which usually only match their components. The handle tie would then become an integral part of the breaker once installed. Here's one, I've often come across breakers tied with solid #10 bare wire put through the holes in the handle and rapped around each handle. Code violation?
 
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Hoodood said:
My interpretation is if one pole trips or is turned off the other pole(s) must also do the same simultaneously. Thereby ensuring all power to the unit has been interupted. Another point concerning breaker ties is does the tie being used have to be made by the same OEM that made the breaker? I would assume so seeing the breakers in a panel must match the panel manufacturers specifications which usually only match their components. The handle tie would then become an integral part of the breaker once installed. Here's one, I've often come across breakers tied with solid #10 bare wire put through the holes in the handle and rapped around each handle. Code violation?
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Your interpretation is incorrect for a circuit that has only line to line loads. There is no need for common trip, as explained by an earlier poster, but if not common trip you do need a handle tie so that manually opening the circuit opens both poles, making it safe for work.
 
electrofelon said:
I dont follow: does a "tight" handle tie make the other pole trip, where a loose one wont?
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I think it would depend if there is enough spring pressure on the tripped handle to pull the other handle enough to operate it. Wouldn't "trip" the second handle if it did this, would just turn it to the "OFF" position.

You can have locking devices on a breaker to keep them "ON" but they still will trip if overcurrent condition exists.

QO has a bar type handle tie now - and is only type available for tying three breakers together. I haven't tried to see if it would take out other breakers if one tripped but something tells me it won't. Tripped QO breaker handle just doesn't put much pressure against a handle tie. Without the trip indicator window you wouldn't know it was tripped either.
 
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