240vcircuit breakerelectricalwiring
Is it possible to put in an electrical circuit without any way to interrupt the circuit?
I tried to work on a 240V outlet, and it wasn't marked in the breaker box. I threw every breaker, and that outlet remained hot. For that matter, there's not a master breaker, either.
The load center with the transfer switch (or "critical load panel") should have a circuit for each circuit that was specified to be connected to the generator. The original breakers no longer function because nothing is connected to them now; there is probably one dual-pole breaker feeding the critical load panel, and there should then be a breaker for each circuit there.
If you are not comfortable investigating, call the electrician that did the install and ask them to walk you through operation and service requirements for the setup.
Since it's a Ground Fault Circuit Interrupter (GFCI) breaker, it's very likely that you have a ground fault.
GFCIs work by detecting an imbalance in current between the ungrounded (hot), and grounded (neutral) conductors. This is why you only see the trip when the circuit is under load. If there is 0 current flow, the current is balanced.
I'd start by inspecting the receptacle. Turn off the breaker, then open up the box where the receptacle is installed. Look for damage to the receptacle itself, or water/moisture in the box.
For outdoor installations you should always have a weatherproof box, and a cover that is weatherproof even when the receptacle is in use.
Best Answer
If there's no main breaker, then there is probably another breaker box somewhere, possibly in the same enclosure as the meter.
Also, it's possible that the panel you are looking at does not have a main breaker at the top; it could be one of the breakers mixed in with the branch circuit breakers. If you can, post a picture of your breaker panel with the cover removed so we can see the wiring inside.