DIYbanter - View Single Post - Strange electric situation

Kevin Ricks

wrote:
I installed a new subpanel and several new circuits in my basement and
just recently passed inspection, fired them up, and they work great.
Last step now is to remove the old lights which hang below the joists
so that I can drywall the ceiling. However, when attempting to cut
off power to these basement lights, I successively turned off every
breaker in the main panel, checked the lights, and they were still
on! Cutting the main power to the panel kills the lights, but no
individual breaker (other than the main) does the trick. Any
suggestions?

Maybe you have a bad breaker that won't switch off.
I would remove the panel cover and test the output of each breaker with
a volt meter or test light to see if they all really go off when turned
off.

Did you shut off all the 240V breakers as well?
Another possibility is an illegal tap from one side of a 220V circuit
like a dryer outlet or water heater or something.

Or maybe you have another old sub panel somewhere?

Kevin