breaker ties

[electricguy61]

Is anyone aware of an issue with using a small piece of wire to tie the poles of (2) side by side twin breakers together for a common trip of a multi-wire circuit? I haven't found a factory made wire tie for the Murray twins.

At times, when you have only a 12/24 panel, breaker space is at a premium, but you don't need a "quad" breaker (that has the breaker tie already installed).

Thanks

 

[Ponchik]

I have used 6/32 screws with nuts and works great.

But I believe Murray does make a quad with (2) handles.

 

[electricguy61]

I have used 6/32 screws with nuts and works great.

Good idea!:happyyes:

 

[jim dungar]

...for a common trip of a multi-wire circuit?

The piece of wire provides for a common switching not a common trip.

These functions are not equal as far as the NEC is concerned.

 

[electricguy61]

The piece of wire provides for a common switching not a common trip.

These functions are not equal as far as the NEC is concerned.

Do you interprete this to mean that breaker ties do not meet the requirement for a multiwire circuit? If the wire is rigid and stays in place, I don't see the difference between it and a breaker tie.

Of course, I'd like to use a breaker tie as opposed to the wire (or 6/32 and nut) if I can find one.

 

[Stevareno]

I had an inspector tell me I couldn't use a piece of wire once -- it wasn't UL listed for the application. This was even before the multi-wire circuit requirement.

I recently had to get some Sqare D breaker ties. They come in a sealed pack of 5 units. When the sales guy quoted $2.95 I thought that was for the pack.
Nope, that's $2.95 apiece! :jawdrop:

What a scheme they have going here. :rant:

 

[infinity]

Handle ties are required to be identified. Does a nut and bolt meet the definition?

240.15(B)(1) Multiwire Branch Circuit. Individual single-pole cir-
cuit breakers, with identified handle ties, shall be permitted
as the protection for each ungrounded conductor of multi-
wire branch circuits that serve only single-phase line-to-
neutral loads.
(2) Grounded Single-Phase Alternating-Current Cir-
cuits. In grounded systems, individual single-pole circuit
breakers rated 120/240 volts ac, with identified handle ties,
shall be permitted as the protection for each ungrounded
conductor for line-to-line connected loads for single-phase
circuits.

Identified (as applied to equipment). Recognizable as
suitable for the specific purpose, function, use, environ-
ment, application, and so forth, where described in a par-
ticular Code requirement.
Informational Note: Some examples of ways to determine
suitability of equipment for a specific purpose, environment,
or application include investigations by a qualified testing
laboratory (listing and labeling), an inspection agency, or other
organizations concerned with product evaluation

 

[jim dungar]

Do you interprete this to mean that breaker ties do not meet the requirement for a multiwire circuit? If the wire is rigid and stays in place, I don't see the difference between it and a breaker tie.

Of course, I'd like to use a breaker tie as opposed to the wire (or 6/32 and nut) if I can find one.

The original question talked about common trip, only now are you mentioning common switching for multi-wire circuits.

Personally I have no problem with field fabricated ties for switching, especially those that are flexible enough to allow independent switching.

 

[kwired]

The original question talked about common trip, only now are you mentioning common switching for multi-wire circuits.

Personally I have no problem with field fabricated ties for switching, especially those that are flexible enough to allow independent switching.

Doesn't independent switching kind of defeat their intended purpose? You have the same thing with no handle tie at all. It is still a potential pain to have to turn off a second breaker just to reset one that tripped though.

 

[jim dungar]

Doesn't independent switching kind of defeat their intended purpose?

What is the intended purpose?

To force them to always operate at the same time or to 'advertize' that a multi-wire circuit exists?

 

[Gregg Harris]

Doesn't independent switching kind of defeat their intended purpose? You have the same thing with no handle tie at all. It is still a potential pain to have to turn off a second breaker just to reset one that tripped though.

there purpose is to allow a simultanious manual disconect of both ungrounded conductors, not simultainious automatic internal disconect.

 

[jim dungar]

... allow a simultanious manual disconect....

Allow or require?

Allow simultaneous means that independent operation is also allowed.
Require simultaneous means that independent is not allowed.

 

[kwired]

there purpose is to allow a simultanious manual disconect of both ungrounded conductors, not simultainious automatic internal disconect.

Tell Jim, that is what I think is intended also. It will not cause "common trip", it is possible for one to trip while other remains energized. You will end up shutting off the energized breaker when attempting to reset the tripped one if the handle tie remains in place during the operation.

 

[kwired]

I could "advertise" a MWBC exists pretty easily with just a label.

 

[Gregg Harris]

Allow or require?

Allow simultaneous means that independent operation is also allowed.
Require simultaneous means that independent is not allowed.

Thank you for the editing Jim, it requires the simultainious manual disconecting of both conductors.

Unfortunatly the misconception of internal automatic interuption of both circuits is common.
One may trip and the other may or may not.

 

[don_resqcapt19]

What is the intended purpose?

To force them to always operate at the same time or to 'advertize' that a multi-wire circuit exists?

My opinion is that the intent is to provide a common means of disconnect.

210.4(B) Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates.

That would not be the case if the handle tie was flexible enough to permit independent operation.

In some cases, especially the case of a two pole QO handle tie, I think that a 6-32 screw and a nut is far superior to the factory identified part. The 3 pole QO handle tie works great, but is of a totally different design from the two pole one.

 

[jim dungar]

My opinion is that the intent is to provide a common means of disconnect.

Even a flexible handle tie can provide this function as well as some independent operation (ala the QO tie you mentioned), which is why the AHJ needs to be the one making the call in the field.

I have been in many panels where the multi-wire circuits were not physically near each other, especially in panels with multiple rows. I seem to recall a double tub panel with one circuit in each tub.

 

[kwired]

Even a flexible handle tie can provide this function as well as some independent operation (ala the QO tie you mentioned), which is why the AHJ needs to be the one making the call in the field.

I have been in many panels where the multi-wire circuits were not physically near each other, especially in panels with multiple rows. I seem to recall a double tub panel with one circuit in each tub.

I have done that myself in the past (but not in separate tubs), but the requirement for handle ties has changed this, unless you can find a handle tie that will work for breakers not adjacent to one another, you will not see that on new installations anymore that are code compliant.