120/12V Step Down Isolation Transformer......

[GoldDigger]

One or two, OK then I would agree but not all 15. I just can't see that possibility on all 15 fixtures especially when conduit is PVC too.

So there is no ground wire running through the PVC to the light fixture? There should have been for the original lights to be legal.
Also, I am not saying it is a defect in the LED unit, I am saying it may be a design feature. That would affect all of them.

 

[chevyx92]

So there is no ground wire running through the PVC to the light fixture? There should have been for the original lights to be legal.
Also, I am not saying it is a defect in the LED unit, I am saying it may be a design feature. That would affect all of them.

Yes the #8 bond is there.

 

[GoldDigger]

Yes the #8 bond is there.

Do the ohmmeter test then....

 

[chevyx92]

Do the ohmmeter test then....

Job is done. Can't.

 

[kwired]

We removed the bonding jumper on secondary side of isolation transformer and it fixed the problem. Fuses don't blow anymore.

There is a ground fault on the opposite secondary lead then. The system is now grounded wherever that fault is.

I disagree with your statement. If there were a fault condition then why did the original incandescent fixtures work? Also this pool has 15 lights, 8 isolation transformers fed from multiple GFCI protected breakers. For your statement to hold any water, every circuit would have to have a fault in it because we had to remove the bonding jumper on every transformer(which isn't required on these isolation type transformers)?

I don't know what you did, but if eliminating the bonding jumper keeps the fuses from blowing it seems fairly obvious that you opened the fault current path when you removed the bonding jumper.

I guess it is not clear if you have a two wire secondary with one side bonded or if you have a three wire secondary with a midpoint bonded.

take some measurements of voltage to ground and consider which conductor the bonding jumper was installed on, if there is now voltage to ground on that secondary conductor but not on another secondary conductor - that one is faulted somewhere.