I want to take 1 and maybe 2 others and connect to an old truck battery to replace their original batteries. the primary one I want to use is like 660VA appears to draw about 25+A from battery. I'd like to put some sort of switch in line with the battery incase I decide to turn it off. I don't have a switch that is capable of like 25A but I remembered I had an old starter relay. thinking maybe I could use that, but not sure of duty on them, and I'm not real crazy that it appears to draw like 4 A just to trigger, and would be all all the time the device is operating think would just use up all power that the charger can put in eventually killing the battery. may just use large alligator clips instead, but would like to know what duty for such relay would be. I know starters are momentary, but not sure if applies to relay also.