If you lose one of the two legs feeding a subpanel then any circuit attached to that leg will de-energize but the circuits on the other leg remain energized.
I wouldn't rule out an iffy main breaker or whatever breaker is feeding your subpanel. I've had many calls where one leg of the breaker feeding a sub was intermittently or completely open. You can probably turn on lights on one of the effected circuits and go out and wiggle the breaker and see, or have someone see, if the lights flicker.
Last edited by ChicoC10; 09/19/07 08:09 PM.
