converter/charger installation instructions

Thanks for replying. For starters,yes,the positive and negatives are simple stuff. There are no batteries hooked up to it,but it does power a 12v fuse block. When I checked the power output I found that there was a line that was hot (powered) hooked up to the system bond lug on the rear of the converter. In my thinking,that should have been a ground wire from the frame. Next off of the fuse panel,there are a heavy red and a heavy black wire ( 10 gauge,stranded) that run to the engine compartment. The red goes somewhere under the dash (haven't been able to find exactly where yet),and the black goes to the positive side of a rely on the firewall. I have been having problems with the engine battery draining and going dead,because of a constant drain of some sort,but there is nothing turned on. I have the van plugged into a 20 amp breaker when not in use,so there should be nothing draining the battery,except whatever is run off of that fuse block and ultimately,the charger/converter. Correct? I would appreciate your opinion and or advise. How was my post posted in the wrong place? Thanks,Bill.