Hoping you all can help me work through an electrical problem I'm having. The problem is my low-voltage niche pool lights are tripping the GFCI breaker that my timer/SWG/heater/pump are connected to. This only happens when turning the lights OFF, and only after turning them on and then off a couple/few times. The lights (and their transformer) are not connected to a GFCI breaker. The light breaker does not trip, nor does the other GFCI breaker (for the service outlet) in the panel.
Here's my setup:
60A 2-pole breaker in my home feeding the sub-panel outside.
20A 2-pole GFCI breaker feeding the pump, timer, heater and SWG.
20A 1-pole breaker to the transformer and 3 niche lights.
20A 1-pole GFCI breaker to the service outlet by the pool.
A picture of the panel is attached.
If I swap the 20A GFCI breaker for a non-GFCI it doesn't trip, however this is a code violation.
This was installed by a licensed electrician, who is aware of the problem and can't figure out what's going on.
So, do we think it's bad lights? A bad transformer? A bad breaker? What could it be?