On 1/20/2016 12:04 AM, E. Robinson wrote:
How do I debug when a circuit breaker keeps tripping?

1. It has never tripped before (years).
2. Yesterday, it was tripped.

"It /was/ tripped" suggests you discovered it tripped; as
opposed to it tripping while you were DOING SOMETHING.

3. I flip it back on, and it trips immediately.

Does "immediately" mean "within a few seconds"? Or, does
it mean "it never actually SETS"? You are REsetting it
before attempting to SET it (i.e., turn it fully OFF, then ON)?

4. It controls a bunch of outlets and lights and that's about it.

Are you positive that there are no other hidden loads?
Doorbell? AC powered smoke detector? Wall clock? etc.

I turn off the lights it controls.
I unplug all the outlets.

How many lights does it control? How many outlets? Are there
other outlets or lights in those rooms that are NOT on the same
circuit?

It still trips.

How do you debug these things?

I asume you want to know how *you* should debug this, not I?

What level of experience with electricity do you have?
And, your personal "Comfort Factor"? How deep is your wallet?
I.e., are you asking out of curiosity? Or, out of *need*
(ABSOLUTELY can't afford to hire someone)?