Breaker Handle Ties

[big john]

I have a 2 pole 30A 240V single-phase breaker enclosure, with two single-pole 15A breakers in it, being fed from two single-pole 20A breakers in a subpanel that is directly adjacent.

Do the two single-pole 20A breakers need a handle tie? I couldn't find anything in code saying they did, and I'm not even sure which article applies. If this is considered a multiwire branch circuit, it seems to me it is allowed to be fed this way. Correct?

Thanks.

-John

[ October 11, 2003, 04:00 PM: Message edited by: big john ]

 

[Guest]

Re: Breaker Handle Ties

210.4(D) would cover the multi-wire circuit tie-bar (handle-tie).

 

[iwire]

Re: Breaker Handle Ties

John what you have is a feeder not a branch circuit, multiwire or otherwise.

Also 240.20(B) requires the breaker to open all ungrounded conductors unless allowed by 240.20(B)(1) or (2) or (3)

I do not believe a handle tie meets this requirement, IMO you need a 2 pole breaker with internal common trip.

A handle tie makes it so when the breaker is operated by hand both breakers work as one, but if a ground fault happens on one pole of a breaker with just a handle tie it may not cause the other pole to open.

Bob

[ October 11, 2003, 04:28 PM: Message edited by: iwire ]

 

[big john]

Re: Breaker Handle Ties

Originally posted by iwire:
John what you have is a feeder not a branch circuit, multiwire or otherwise.

Right you are. Man, sometimes I wonder where my brain is... :roll:

Thanks.

-John

 

[pierre]

Re: Breaker Handle Ties

Bob
If you read the complete text of 240.20(B)(1), (2), & (3) The use of 'approved handle ties' is part of the text.

Truth be known, single pole breakers and two pole breakers are tested differently, and using a single pole breaker with handle ties may not afford the same protection. But the NEC permits it.

Pierre

[ October 12, 2003, 12:03 AM: Message edited by: pierre ]

 

[big john]

Re: Breaker Handle Ties

Originally posted by pierre:
...And using a single pole breaker with handle ties may not afford the same protection. But the NEC permits it.

I was going to site 240.20(B) as a contradiction to that statement, but reading in reading it again, there seems to be some ambiguity:

240.20(B):
Circuit breakers shall open all ungrounded conductors of the same circuit unless otherwise permitted in 240.20(B)(1-3)

That does not say that all conductors must be opened simultaneously, simply that they must be opened. Mind you, I think it's good practice to install common-trip breakers on feeders, but I don't interpret 240.20(B) as requiring it.

Opinions?

-John

 

[pierre]

Re: Breaker Handle Ties

240.20(B)(1),(2),&(3) are instances in their respective sections that require simultaneous opening of the OCPDs in each phase.

Pierre

 

[big john]

Re: Breaker Handle Ties

Pierre,

I agree to that, but what about feeders that don't originate from service equipment, as well as other examples that don't fall under 240.20(B)(1-3)? I have not yet found anything that seems to prohibit the independent disconnection of each ungrounded conductor.

-John

 

[pierre]

Re: Breaker Handle Ties

215.3 Overcurrent Protection.
Article 215 is for feeders.

This section refers you back to Part I of Article 240. Part I brings us back to 240.20 .

Pierre

 

[tonyi]

Re: Breaker Handle Ties

Originally posted by pierre:
240.20(B)(1),(2),&(3) are instances in their respective sections that require simultaneous opening of the OCPDs in each phase.

Pierre

Actually I think it applies to breakers, not OCPD's in their most generic sense (ex. a pair of fuses). An older 150A GE panel in my parent's old homestead up north has a fused pullout main disconnect with THQL/TQL type push on breakers. An overload on one leg will only blow that leg's 150A fuse. Similarly, a fused disconnect upstream of an MLO panel could chop just one leg in the MLO on an overload.

Simultaneous trip isn't precisely the same thing as simultaneous disconnect.

 

[iwire]

Re: Breaker Handle Ties

Originally posted by pierre:
Bob
If you read the complete text of 240.20(B)(1), (2), & (3) The use of 'approved handle ties' is part of the text.

Hi Pierre, Maybe I did not explain myself well, here is what I said earlier with some bolding.

Quote by me

240.20(B) requires the breaker to open all ungrounded conductors unless allowed by 240.20(B)(1) or (2) or (3)

And for comparison the actual code text.

240.20(B) Circuit Breaker as Overcurrent Device. Circuit breakers shall open all ungrounded conductors of the circuit unless otherwise permitted in 240.20(B)(1), (B)(2), and (B)(3).

There is no reference to handle ties in 240.20(B), it says circuit breakers shall open all ungrounded conductors of the circuit, not circuit breakers with handle ties.

To me this leaves internal trip breakers as the only way to comply with 240.20(B) itself.

Big Johns question was about a feeder that serves line to neutral loads so only 240.20(B) is relevant, he does not meet the criteria of parts 1, 2, or 3

Big Johns circuit was not a Multiwire Branch Circuit so 240.20(B)(1) is not relevant

Big Johns circuit is closest to meeting the requirements of 240.20(B)(2) Single-Phase and 3-wire dc Circuits. If he did meet all the requirements of this section handle ties would clearly be allowed.

240.20(B)(2)

(2) Grounded Single-Phase and 3-wire dc Circuits. In grounded systems, individual single-pole circuit breakers with approved handle ties shall be permitted as the protection for each ungrounded conductor for line-to-line connected loads for single-phase circuits or 3-wire, direct-current circuits.

Big Johns circuit is certainly grounded single phase but it does not serve line to line loads

His circuit as described serves line to neutral loads, so IMO that makes 240.20(B)(2) irrelevant in this case.

240.(B)(3) 3-Phase and 2-Phase Systems, is also not relevant in Big Johns circuit.

Bob

[ October 12, 2003, 05:37 AM: Message edited by: iwire ]

 

[templdl]

Re: Breaker Handle Ties

What you are looking for is the designation "common trip."
Some manufactures will make a multipole breaker in a sigle from with one handle while others will assemble 2 or more single pole frames together where the manufacturer adds an internal common trip bar internal to the assembly that will trip all poles if one pole trips calls for a trip. This breaker will look like 2 or more single pole breakers operated with a handle tie but look for the designation "common trip."

 

[charlie]

Re: Breaker Handle Ties

I have intended to stay out of this one because of my membership on CMP 10. This is not an official interpretation nor an opinion of the panel, this is just my opinion.

IMO, Bob and templdl are correct. The intent of handle ties are to provide a means for common switching, not for common tripping. Some circuits are fine to have a single OC device open the circuit leg and not the whole circuit. If it were a big problem, the Code would require common trip fuses. Please reread what Bob (iwire) and templdl have written, they have a handle (pun intended) on this issue,