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#109169 - 10/20/03 04:54 PM # 12 THHN used as handle tie
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I don't believe the wire is strong enough to trip both breakers, if suppose one of them were to trip?

-richard

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#109170 - 10/21/03 08:49 AM Re: # 12 THHN used as handle tie
resqcapt19 Offline
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Handle ties are not intented to provide a common trip. They are only intended to provide a common disconnect. The code code permits "approved" handle ties in 240.20(B), but I doubt that the AHJ has approved the wire as a handle tie. Even the handle ties from the breaker manufacturer do not turn 2 breakers into a "common trip" breaker.
Don
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#109171 - 10/24/03 09:01 PM Re: # 12 THHN used as handle tie
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Here's another Photo sent in with a question along the same lines:

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Is it illegal to take two single-pole breakers and link them together with a piece of copper wire and use them as a two-pole breaker for a 220V application? Is it safety hazard? Look at breakers 7 and 9 in the power panel.

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#109172 - 10/25/03 08:34 AM Re: # 12 THHN used as handle tie
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In this second case 240.20(B) requires the use of a common trip breaker. The use of approved handle ties is not permitted for this application. If these breakers were serving a multiwire branch circuit and not a 220 volt load the use of approved handle ties would be permitted by 240.20(B)(1).
As far as a safety hazard, I don't think so. The same condition would exist if the OCPDs were fuses in place of the single pole breakers and fuses are premitted to protect this circuit.
Don
corrected my code section reference from 240.21 to 240.20

[This message has been edited by resqcapt19 (edited 10-27-2003).]
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#109173 - 10/25/03 05:23 PM Re: # 12 THHN used as handle tie
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resqcapt19:

Thanks for the explanation.

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#109174 - 10/26/03 10:14 PM Re: # 12 THHN used as handle tie
sparky74 Offline
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Registered: 05/08/03
Posts: 8
Loc: Naples, Italy
So for a 220V load, a two-pole breaker must be used--period! Correct?

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#109175 - 10/27/03 04:15 AM Re: # 12 THHN used as handle tie
resqcapt19 Offline
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Registered: 11/10/00
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Sparky,
Sorry, I misspoke in the earlier post. On a grounded single phase circuit the code does permit the use of single pole breakers with handle ties for 220 volt loads.
 Quote:
240.20(B)(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).
(1) Multiwire Branch Circuit. Except where limited by 210.4(B), individual single-pole circuit breakers, with or without approved handle ties, shall be permitted as the protection for each ungrounded conductor of multiwire branch circuits that serve only single-phase line-to-neutral loads.
(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.
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#109176 - 10/27/03 05:45 AM Re: # 12 THHN used as handle tie
sparky74 Offline
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Registered: 05/08/03
Posts: 8
Loc: Naples, Italy
resqcapt19:

Thanks a lot for the info. I guess the only discrepency is that, the piece of copper wire is not an "approved" handle tie.

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#109177 - 10/27/03 08:12 AM Re: # 12 THHN used as handle tie
resqcapt19 Offline
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Registered: 11/10/00
Posts: 2209
Loc: IL
Sparky,
You would have to ask the AHJ about that. He can "approve" the wire if he want to.
Don
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