Internal trip mechanism required?

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Coppersmith

Coppersmith

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Tampa, FL, USA
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Electrical Contractor
I have two single pole breakers connected with a listed handle tie. The inspector is failing it because he says it has to have a connected internal trip mechanism. I believe he is wrong but I can't find code to support me. Being used on an air conditioning circuit.
 
Is this it? Note I'm on 2014 NEC.

240.15(B)(2) Grounded Single-Phase Alternating-Current Circuits.
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.

Says breakers rated 120/240. That's not a normal breaker is it?


Also found this which contra-indicates. Is a two pole breaker the same as parallel breakers?

240.8 Fuses or Circuit Breakers in Parallel. Fuses and
circuit breakers shall be permitted to be connected in parallel
where they are factory assembled in parallel and listed
as a unit. Individual fuses, circuit breakers, or combinations
thereof shall not otherwise be connected in parallel.
 
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I agree that he is wrong. The purpose of the listed handle tie is not to make sure both breakers trip when one has a high current. The purpose is to make sure both are off when you want to turn one off for maintenance. 210.4(B) has your answer. It requires a means for simultaneously disconnecting all ungrounded conductors. That is a manual action, not an automatic protective action.
 
Simply put, overload/short operation requires the internal trip, manual disconnect is satisfied by the handle tie.

The difference depends on whether you're supplying any line-to-line loads, or only line-to-neutral loads.

Coppersmith said:
Being used on an air conditioning circuit.
Click to expand...
This means the inspector is correct in this case.
 
charlie b said:
I agree that he is wrong. The purpose of the listed handle tie is not to make sure both breakers trip when one has a high current. The purpose is to make sure both are off when you want to turn one off for maintenance. 210.4(B) has your answer. It requires a means for simultaneously disconnecting all ungrounded conductors. That is a manual action, not an automatic protective action.
Click to expand...
Does it matter that this is a line-to-line load?
 
LarryFine said:
Simply put, overload/short operation requires the internal trip, manual disconnect is satisfied by the handle tie.

The difference depends on whether you're supplying any line-to-line loads, or only line-to-neutral loads.


This means the inspector is correct in this case.
Click to expand...
That's the key distinction what is the type of load. Line to line handle ties are permitted.
 
The key to applying all that has gone by is whether the AC in question is indeed a line to line only load or has any components, like fans, relays, and controls that are fed line to neutral (120V). If there is no neutral connection to the AC unit (only an EGC), then you can be sure that it contains only line to line loads. If there is a neutral connection too, you cannot be sure based on that alone whether there are any line to neutral loads.
 
GoldDigger said:
The key to applying all that has gone by is whether the AC in question is indeed a line to line only load or has any components, like fans, relays, and controls that are fed line to neutral (120V). If there is no neutral connection to the AC unit (only an EGC), then you can be sure that it contains only line to line loads. If there is a neutral connection too, you cannot be sure based on that alone whether there are any line to neutral loads.
Click to expand...
There is no neutral.
 
LarryFine said:
I guess they DO consider the handle tie adequate to open both/all poles upon one tripping.
Click to expand...
Are you sure Larry? Note that 240.15(B)(2) above specifies slash rated breakers so I'm not sure it applies to non slash rated breakers. You might have been right the first time. I'm just confused.
 
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