Gfci trips

[boston62]

I swapped out my old breaker, with gfci breaker, but when I go to turn on light it trips. My old breaker had just the hot sire going to it, but no white neutral wire. The new gfci had the hot & coiled wire which h I connected to the neutral bar, there is a screw on the gfci for a neutral wire but non on the old one. Here is the gfvi inztalled..Any ideas? Tank you.

 

[JohnT]

You need to connect the neutral wire that feeds your light to the neutral screw on the breaker.

A GFCI works by comparing the current in the neutral wire going to the circuit and the hot wire going to the circuit, so they both have to feed through the breaker. The neutral pigtail is the input for the breaker and the screw is the output.

 

[JasonLion]

With a 115 volt GFCI breaker you need to connect the neutral line coming from the light to the neutral connection on the breaker, and then the coiled wire on breaker goes to the neutral bus. This is different from a non-GFCI breaker, where the neutral from the light goes straight to the neutral bus.

 

[boston62]

So i have to fish a white wire from the light transformer to the subpanel, can i just join it to the other white wires in the transformer, then fish it over to the subpanel?

 

[boston62]

The white wire stops at the tranformer...12v

 

[JohnT]

So i have to fish a white wire from the light transformer to the subpanel, can i just join it to the other white wires in the transformer, then fish it over to the subpanel?

No, there is a white wire feeding your circuit in the breaker box already. That wire needs to connect to your GFCI breaker.

A standard 120V circuit has three wires from the breaker box to the equipment: Black hot, white neutral and bare ground. In your case the equipment is the transformer.

 

[jblizzle]

There can not just be a single power line running from the breaker to the transformer. There must be a neutral to complete the circuit.

You make it sound like the transformer neutral might be tied into the neutral for some other circuit. If that is the case, not sure a GFCI breaker is going to work correctly ... unless you run a dedicated neutral wire.

 

[JasonLion]

To put that another way, there must already be three wires, hot neutral and ground, running from the breaker panel to the transformer. You want to connect the breaker panel end of the existing neutral wire to the GFCI breaker, instead of directly to the neutral bus bar.

 

[boston62]

I did it, what was confusing the black wire comes in then goes over to the relay load, then back over to subpanel, i found the white wire by looking in the conduit where the light comes over from transformer. Thanks everyone

 

[JohnT]

I did it, what was confusing the black wire comes in then goes over to the relay load, then back over to subpanel, i found the white wire by looking in the conduit where the light comes over from transformer. All fixed.. thanks everyone...

Nice to have 75,000 friends to ask for advice when you are working on the pool!

 

[boston62]

Yes it is, and it is appreciated. ..