First: my assumptions: It is the DC and not the AC side that is out. The is no DC power to the panel at all. The genset is an AC genset. The first thing I would look for is a large in-line fuse in the system. One should be located near the charger or charger/inverter on the DC hot side of your house bank. If that is OK, look behind the battery selector switch for any fuses. Good luck. Let us know what you figure out.