The only way to get a 90% charge on the deep cycle batteries in a three hour time period without gassing out battery fluids is to use 14.4VDC for two hours and 13.6VDC for the remaining one hour...
I believe I have read where some of the guys that live full time in their trailers do just that with two or three VEC1093DBD Portable smart mode chargers in use in parallel...
I would just get a good quality smart mode 40AMP Battery Charger like the B&D VEC1093DBD and just plug it into the generator and direct connect to the disconnected battery terminal to charge them back up in the three hours until you can replace the WFCO products...
I wired in a PRD9260C 60A Smar Mode charger in the same daisy chain battery feed line on my setup and then just turn on the proper circuit breaker to use either the WFCO unit or the PD9260C unit. My PD9260C has the double DC CONNECTOR to allow for daisy chaining the 4WG DC cables. My WF-8945 was brand new and I hated to just throw it away so now it is used as a standby unit. When camping off the power grid I totally use the PD9260C which goes into smart mode charging when you want it to...
My wiring setup looks like this using both the WF8945 and the PD9260C...
Roy Ken
