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Joined: Mar 2003
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When are tie handles between single pole circuit breakers not approved?
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Joined: Jan 2005
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ANS: When a "common trip" breaker is required by the NEC. Handle ties are only used when one wants to assure that (2) adjacent 1p breaker are to be manually opened and closed at the same time. Handle ties ARE NOT A SUBSITUTE for 2p or 3p common trip breakers that look like they are tied together with only a handle tie.
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So, you could use them in a situation where two outlets in the same box are on different circuts?
Proud Inventor of the Three Phase Light Bulb!
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See NEC 210.4 (B) 2002. If they share a common grounded conductor they must be 2 pole not handle tied. Alan--
Alan-- If it was easy, anyone could do it.
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GTE When are tie handles between single pole circuit breakers not approved? I want to be sure we know what your asking. Dave T gave a good answer if the question is 'When can a handle tie be used?' However I was wondering if your question is 'What is an approved handle tie?' Alan 210.4(B) 2002 210.4(B) Dwelling Units. In dwelling units, a multiwire branch circuit supplying more than one device or equipment on the same yoke shall be provided with a means to disconnect simultaneously all ungrounded conductors at the panelboard where the branch circuit originated. All that section requires is a 'means to disconnect simultaneously all ungrounded conductors at the panelboard'. Here is a handbook image which shows it much better than I could draw it. IMO the handbook image is directly supported by the text of 210.4(B) [This message has been edited by iwire (edited 04-08-2006).]
Bob Badger Construction & Maintenance Electrician Massachusetts
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Handle ties are also used to meet the 6 disconnecting means rule:
NEC 2005:
230.71 Maximum Number of Disconnects. (A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception Nos. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be not more than six sets of disconnects per service grouped in any one location. For the purpose of this section, disconnecting means used solely for power monitoring equipment, transient voltage surge suppressors, or the control circuit of the ground-fault protection system or power-operable service disconnecting means, installed as part of the listed equipment, shall not be considered a service disconnecting means. (B) Single-Pole Units. Two or three single-pole switches or breakers, capable of individual operation, shall be permitted on multiwire circuits, one pole for each ungrounded conductor, as one multipole disconnect, provided they are equipped with handle ties or a master handle to disconnect all conductors of the service with no more than six operations of the hand.
fixed speling
[This message has been edited by jfwayer (edited 04-08-2006).]
JFW
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Iwire. What I wanted to know is when do have to use a 2-pole breaker or when tie handles are not allowed?
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The answer has been given, although maybe not clearly.
If the situation requires a simultaneous disconnect, as in manual operation, a handle tie is adequate. In fact, the disconnect need not be a breaker.
However, if simultaneous over-current protection is required, then a 2- or 3-pole breaker must be used. The handle tie is not what makes all handles trip.
If you want every situation that requires one over the other spelled out, I don't think we'll be doing that here. Maybe you can tell us your specific situation.
Larry Fine Fine Electric Co. fineelectricco.com
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Iwire. What I wanted to know is when do have to use a 2-pole breaker or when tie handles are not allowed? OK I think I can help out. 240.20 Ungrounded Conductors. (A) Overcurrent Device Required.
A fuse or an overcurrent trip unit of a circuit breaker shall be connected in series with each ungrounded conductor. A combination of a current transformer and overcurrent relay shall be considered equivalent to an overcurrent trip unit. FPN:For motor circuits, see Parts III, IV, V, and X of Article 430.
(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.
(3) 3-Phase and 2-Phase Systems. For line-to-line loads in 4-wire, 3-phase systems or 5-wire, 2-phase systems having a grounded neutral and no conductor operating at a voltage greater than permitted in 210.6, individual single-pole circuit breakers with approved handle ties shall be permitted as the protection for each ungrounded conductor. Examples of circuits in which approved handle ties are permitted according to 240.20(B)(2) or 240.20(B)(3). It is interesting to note that we can use handle ties on loads such as dryers and ranges. I think most of us assume a common trip breaker is required. [This message has been edited by iwire (edited 04-09-2006).]
Bob Badger Construction & Maintenance Electrician Massachusetts
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Original question... "When are tie handles between single pole circuit breakers not approved?" When the "handle tie" is a nail, wire or other garbage someone dropped in the holes in the handles. An approved one, would be one made for the purpose by the manufacturer for that type of breaker.
Mark Heller "Well - I oughta....." -Jackie Gleason
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Tom
Shinnston, WV USA
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