Using two pole breaker for single pole

Status
Not open for further replies.
S

Stevenfyeager

Senior Member
Location
United States, Indiana
Occupation
electrical contractor
Is it ok to take one wire off a two pole breaker and use it as a single pole? I’ve heard that it will still trip ok as if it’s a single pole breaker but I have never done that. Or do you have to remove the connecting bar on the breaker for it to work? And then if I do that, does that void a warranty or go against manufacturer or against code ? Thank you.
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
It will work just fine, each pole has its own trip sensing, they are just internally tied together so that if one trips, it opens both. No need to remove the handle clip, in fact I would purposely leave it so that the next person understands that it is a 2 pole breaker, not two separate one pole. The only drawback is that its a waste of space, but in a pinch, I've done it (as have many others).
 
G

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
marmathsen said:
Is it actually internal? I always thought it was simply the handle tie that facilitated the simultaneous trip.
Click to expand...
Not at all.
The breakers are required to be able to trip even the handle is held in the open position and there is also no way to manually move the handle to the tripped position rather than the open position.
What the handle tie does is something that the internal trip cannot do, namely make it impossible to manually turn off just one pole.

Sent from my Pixel 4a using Tapatalk
 
M

marmathsen

Senior Member
Location
Seattle, Wa ...ish
Occupation
Electrical Contractor
GoldDigger said:
Not at all.
The breakers are required to be able to trip even the handle is held in the open position and there is also no way to manually move the handle to the tripped position rather than the open position.
What the handle tie does is something that the internal trip cannot do, namely make it impossible to manually turn off just one pole.

Sent from my Pixel 4a using Tapatalk
Click to expand...
Makes sense. All off this was stuff I have known but I guess I hadn't really thought hard enough to realize that the handle tie couldn't be the means of simultaneous trip. Not if the breaker is capable of tripping in spite of being held in the on position. Thanks again for the education.

Rob
 
don_resqcapt19

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
GoldDigger said:
Not at all.
The breakers are required to be able to trip even the handle is held in the open position ...
Click to expand...
And this requires the breaker to be of the "trip free" design. I have always thought that that was a strange name for this function.
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
don_resqcapt19 said:
And this requires the breaker to be of the "trip free" design. I have always thought that that was a strange name for this function.
Click to expand...
Yes, isn't it? There must be some sort of history as to how that terminology came to be. It's not intuitive. "Trip-free" congers up the image of a breaker that is "free from tripping", i.e. a Molded Case Switch. I've imagined that it means "free to trip", meaning you can't wedge something in the handle to try to prevent it from tripping, it is "free to trip" regardless of what you try to do to it. How that became "trip-free" though eludes me.
 
R

robertd

Senior Member
Location
Maryland
Occupation
electrical contractor
Jraef said:
Yes, isn't it? There must be some sort of history as to how that terminology came to be. It's not intuitive. "Trip-free" congers up the image of a breaker that is "free from tripping", i.e. a Molded Case Switch. I've imagined that it means "free to trip", meaning you can't wedge something in the handle to try to prevent it from tripping, it is "free to trip" regardless of what you try to do to it. How that became "trip-free" though eludes me.
Click to expand...
>free from tripping
That would be a FPE stab-loc :)

Google "non trip free circuit breaker" and one of the first links is https://www.tpub.com/neets/book3/8k.htm
Which has:
"A trip-free circuit breaker is a circuit breaker that will trip (open) even if the operating mechanism (ON-OFF switch) is held in the ON position. A nontrip-free circuit breaker can be reset and/or held ON even if an overload or excessive heat condition is present. In other words, a nontrip-free circuit breaker can be bypassed by holding the operating mechanism ON. " (My bold)

That does not sound like a good idea.

And:
"Nontrip-free circuit breakers are used for circuits that are essential for operations. Examples of these circuits are emergency lighting, required control circuits, and essential equipment circuits."

Your essential circuit is of no use if it burns up.
 
Status
Not open for further replies.
Top