When my 4 ton central a/c unit turns on, the lights dim for just a second as the unit turns on. The a/c has been serviced and is in good woking order. The main ground from my electrical panel is connected to the ground rod. What can cause this and what if anything can fix it.

Thanks, Robert

The compressor draws about four times the rated amp draw on startup, this is what pulls the voltage down momentarily, you could add a start kit to the compressor to help in starting the compressor and see if that does it, good luck, Mike

It's normal!