GFCI Breaker on Grounded "B" Service for Heat Tape

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Silvertaco81

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Genesee, wisconsin, Usa
I Have a customer who has a 240V Grounded B Service. He has some Gutter heating tape on a 2 pole 30 Gfci Breaker.. Now last year Winter 2023 jan-april. he mention to me that occasionally the breaker would be tripped. Not sure if it is a Gfci trip or a over current trip. i went to examine the trace and it is only 20 amps of load, there are no knicks in the wire and the Feed end and the Finish end is properly terminated. this is self regulating heat tape. My questions,
A. is this suppose to be on a Grounded B Service,
B. should i take off the Gfci Protection Cause this is on a Gfci Service.
This is in Wisconsin Where this service type is normal but not installed on new buildings anymore
 
I do not know of any residential style GF breaker rated for 240V to ground. I would be concerned with the white pig tail lead and the 'slash rating' of the assembly.
A GFCI with a 5mA trip level may nuisance trip on heat trace. You may need to use an external 30mA sensor with a shunt trip breaker.
 
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Silvertaco81 said:
I Have a customer who has a 240V Grounded B Service. He has some Gutter heating tape on a 2 pole 30 Gfci Breaker.. Now last year Winter 2023 jan-april. he mention to me that occasionally the breaker would be tripped. Not sure if it is a Gfci trip or a over current trip. i went to examine the trace and it is only 20 amps of load, there are no knicks in the wire and the Feed end and the Finish end is properly terminated. this is self regulating heat tape. My questions,
A. is this suppose to be on a Grounded B Service,
B. should i take off the Gfci Protection Cause this is on a Gfci Service.
This is in Wisconsin Where this service type is normal but not installed on new buildings anymore
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Are you sure this is a ground fault protected service? Not that it would matter as far as the heat trace is concerned, as the trip level would be in amps, not milliamps. It may be an ungrounded service with a fault on B phase. If an ungrounded service, it should have a fault detector. As others have said, the breaker may not be rated for 240 to ground.
 
I'm fairly certain you won't find a GFCI that doesn't need 120 volt for the neutral pigtail to connect to, I kind of doubt you will will find a straight 240 volt GFPE breaker either. OP are you sure you don't have a high leg delta and not a grounded B phase ? Some seem to get confused with delta system possibilities but a high leg delta does still have 120 volts to ground on two lines and would work with what you described having.
 
ABB has single pole breakers with 30mA ground fault and supplementary overload protection that can accommodate 240V L-N at 60 Hz, and they have UL 1053 and UL 1077 (UL recognized) approvals. But they would require a panel builder to incorporate them into a listed assembly. Obviously they are a spin-off of their IEC compliant breakers.

https://library.e.abb.com/public/3ab857e988284bc9a4697b6cd127b052/DS201 UL RCBOs Customer presentation Rev.A Jan.2023.pdf

https://library.e.abb.com/public/06753c5c372a4ce3a8fb200099a9c3d8/9AKK108467A7072 DS201 UL RCBOs REV.A JAN 2023.pdf
 
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