I am no electrician by any means but I have ran thousands of feet of wire, hooked up receptacles, lights, hot water heaters, breakers, etc... the average things with never an issue. I ran some new recessed lighting in a old basement. 4 lights 2 switches to be exact. I first ran a wire to each switch from desired ceiling location of first can and then the same with the other switch. Each switch is running 2 lights. 1 located in back of room one in front (so they can dim lights separately). I then ran a wire from each switch to a junction box in ceiling from hallway from here I ran a home run to main box and added a new 20 amp breaker.
I went to go hook up dimming switches and the first set I hooked up no problem... walked to the other side hook up my neutral, hot and then while I hooked up my ground it popped the breaker. I sat there dumbfounded for the better of 30 minutes trying too determine what went wrong. I hooked everything up excluding the ground and it all works but the moment the ground from the 12/2 going to light touches the ground going to the junction box it fails me. I then started further testing and found that my chirper will go off anywhere on that side of the room if near the drop ceiling rail. I know this is quite scary! Its not until I touched an old junction box in the ceiling with my hammer at the same time as the drop ceiling rail did I realize it was actually live. Ive spoke with a few knowledgeable electricians and they said it was most likely an old issue sending residual current back through the ground.
If this is in fact a great possibility then how and where do I start too look and solve this grave issue? If not, what is the next plausible issue?
Note: In new junction box I just connected black/black white/white ground/ground. In breaker there is a shared bar with both ground and neutral wires connected. Inside the can lights there is quick connectors that I cut and used wire nuts but I have rechecked this several times and everything seems correct.