GFCI Breakers and no nuetral

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rgoodwinelectric

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I'm currently in Afganistan and was told to install a GFCI Circuit breaker for the water heater circuit. The circuit is a 208v circuit with no nuetral/ only 2 hots and ground. I was given a box of 120v single phase GFCI breakers. I know this is an odd questions, but will this application work using two 120v GFCI breakers to protect a 208v circuit with no Nuetral ? (I'm aware there is no common trip)
 
It will not work unless they are GE brand. Most manufacturers sell a DP GFCI. The neutral from the breaker gets connected to the neutral bar but no neutral is needed at the equipment.

Ge is the only manufacturer that can use 2 sp gfci breakers that will work together with a handle tie as a dp breaker.
 
Dennis Alwon said:
It will not work unless they are GE brand. Most manufacturers sell a DP GFCI. The neutral from the breaker gets connected to the neutral bar but no neutral is needed at the equipment.

Ge is the only manufacturer that can use 2 sp gfci breakers that will work together with a handle tie as a dp breaker.
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Can you tell us why that will work?

Each one will have an unbalanced current passing through the sensing core and should trip.
 
Dennis Alwon said:
Ge is the only manufacturer that can use 2 sp gfci breakers that will work together with a handle tie as a dp breaker.
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Dennis, I know that's true for GE MOD 3 single pole AFCIs, but wasn't aware that GE GFCIs had changed also. Is this true that GE GFCIs don't require a nuetral connection?

Ah. Already asked and aswered. Thanks, Dennis.
 
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al hildenbrand said:
Dennis, I know that's true for GE MOD 3 single pole AFCIs, but wasn't aware that GE GFCIs had changed also. Is this true that GE GFCIs don't require a nuetral connection?
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Again my error but no neutral is needed on any DP GFCI. We see it all the time with hot tubs. I need to go eat breakfast.. :grin:
 
Gfci breaker

Gfci breaker

If I tie the breakers together, if there is a ground fault by either line it would still open the circuit at designated time/sens of the manufacturer.. As I understand it, the only thing a GFCI breaker does that a regular breaker doesn't is it measure an unbalanced load between nuetral and line, ... still the same, if a ground fault occurs it should still open the circuit at a much quicker rate (3-5 Ma/ 25ms) which still serves its purpose ?
 
rgoodwinelectric said:
If I tie the breakers together, if there is a ground fault by either line it would still open the circuit at designated time/sens of the manufacturer.. As I understand it, the only thing a GFCI breaker does that a regular breaker doesn't is it measure an unbalanced load between nuetral and line, ... still the same, if a ground fault occurs it should still open the circuit at a much quicker rate (3-5 Ma/ 25ms) which still serves its purpose ?
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A sp breaker that is gfci will look for the difference in amps coming in and going out. If there is a 5 ma difference it will trip. How would you accomplish this with 2 sp breakers. The reason the AFCI works with 2 sp units is because ge took the gfci protection out of the afci breakers, I believe.
 
rgoodwinelectric said:
If I tie the breakers together, if there is a ground fault by either line it would still open the circuit at designated time/sens of the manufacturer.. As I understand it, the only thing a GFCI breaker does that a regular breaker doesn't is it measure an unbalanced load between nuetral and line, ... still the same, if a ground fault occurs it should still open the circuit at a much quicker rate (3-5 Ma/ 25ms) which still serves its purpose ?
Click to expand...
Using two single pole GFCIs with a handle tie on a double pole load (that has no neutral) will result in the breaker(s) immediately tripping every time you turn them on when the load is drawing current.


Think about what you understand about the operation of a single pole GFCI . . . it is correct. In a single pole, the current leaving the breaker on the hot is measured against the current returning on the neutral.

Hooked up to the load as you propose, each single pole breaker will always try to trip every time the load trys to draw current, because there is no way for the return current to be on that single pole breaker's neutral.

The two single pole breakers will compete to be the first to trip, interrupting the current, and sometimes one, or the other, or both breakers will actually trip.

Bottom line, you'll never be able to turn on the load.
 
kwired said:
Each one will have an unbalanced current passing through the sensing core and should trip.
Click to expand...

Dennis Alwon said:
Again my error but no neutral is needed on any DP GFCI. We see it all the time with hot tubs.
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A 2p GFCI breaker passes both lines through the same current sensor. That cannot happen with two 1p units.
 
LarryFine said:
A 2p GFCI breaker passes both lines through the same current sensor. That cannot happen with two 1p units.
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Correction a 2 pole GFCI breaker passes both lines and the the neutral through the same current sensor. If all current that leaves one conductor returns on one or both of the other conductors the sensing coil sees no voltage and does not activate trip device.
 
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