The assignment varies depending on your equipment. For instance, if you have a factory-installed all-outlets inverter there will be a single large breaker to feed the sub-panel (labelled "transfer switch"), but if you don't there will be individual branch circuit breakers (normally two). Both air conditioning and the electric heat option for the water heater add breakers, and they are not typically the bottom ones on the panel. Some owners have shared photos of their panels with labels, but I would ask ETI to provide the information, and labels.
Here's an example from the topic 21' electrical photos
, provided by Cathy in post #25
It might be reasonable to assume that another trailer with the same equipment combination would have the same position assignment, and it would be easier to confirm that than to start from scratch.
- the main breaker is in the top position
- the converter and refrigerator share the first (top) branch circuit breaker
- the air conditioner circuit is the only one with a 20-amp breaker
- the inverter sub-panel / transfer switch circuit is the only 30-amp breaker
I haven't noticed if there is any consistent pattern to fuse assignment; it doesn't come up for discussion as an issue very often, while the inverter and transfer switch configuration has.
Another new owner is also missing the labels, so i think ETI needs to know that there has been a production issue:
AC not cooling / Fuse locations/purpose