OTRFUN - The idea is to "never never never" let your battery get below 12.0VDC... This is around the 50% charge state. If it gets to 10.5VDC it is 0% charge state. If they get down to 5V, 6V etc they will start self destruct mode inside and you will have to replace them.. i.e they will be hard to recover if they get that low in DC voltage...
I have a DC VOLTMETER monitoring my batteries at all times when in use and my game plan is to never let them get below the 50% charge state or around 12.0VDC... They will recover if you let them get down to 10.5VDC but that is flirting with battery death in my book...
I think most of the battery expert guys on here are in agreement with this...
You need to get a DC SHUNT installed inline with battery so you can monitor. If that is out of the picture you can pickup a CLAMP ON DC (Note I said DC) ammeter. Sears sells one for around $50 I think... The only I ever read the AV AMPS on the 120VAC side is to make sure my 2KW Honda Generator will operate my converter/charger. My PD9260C draws are 1000WATTs on the AC side when the output is loaded down to 60AMPS.
I think you really need to think about changing out your WFCO WF8955 controller/charger with a good PD or IOTA model unit.. I left my WF8945 COnverter in the power distribution panel and just turned it off. Then I mounted my PD9260C unit closer to the battery bank. I can now use either one by just flipping the correct circuit breaker. Its a backup thing. Even tho it won't go into smart charge mode it does still put out 13.6VDC and will run my DC requirements on the trailer. Just can't use it when charging my batteries.
Roy Ken