I posted this under General Topics but here may be a better location. I really need some help/ideas.
I have a new P-C 690LR router. To do a tool zero, I put a clip on the bit and G31 down to the touch pad. The routine wasn't working. I tested the circuit by touching the clip to the pad and the circuit worked fine. As I continued to work with it, I noticed that touching the clip to the bit was causing sparks! Never had that happen before. The clip is connected to 5V and the zero pad is connected to pin #11 (C10). The touch pad works flawlessly with other routers. The computer, electronics and router have a common ground.
I used a voltmeter to do some testing.
1. There is a 6v DC flow when touching the 5V clip to the router body when the router is plugged in (but turned off). It's the same whether plugged into the Relay Board or directly to a wall socket. This makes some sense as I am connecting 5V DC to ground.
2. The voltmeter also shows a small AC voltage. This is puzzling as the Relay Board is switching the black wire so logically there is not an AC circuit unless there is a current leak between the common and ground wires.
3. I have a solid ground among all the parts. The Ohm meter show 0 between the router body/bit and the table. The ground between the router and table also exists when the router is plugged into the wall socket. I have what Al calls a "ground star".
I'm thinking the sparks are caused by the 5V DC C10 circuits coming in contact with a small AC charge. Although the router will start and run, I am thinking it may have an internal short/electrical issue somewhere and that I should return it. Anyone have any thoughts?
Thanks for your ideas.
Dave