Re: Battery switch
A battery switch provides several capabilities but the main reason for having it is to protect the start battery from being drained by house or accessory loads such as radios, depth finders, trolling motors, etc. OFF obvisously turns off all electrical power and would be used at the dock when you are not there. The bilge pump should be connected directly to the battery so it is able to operate.
Normally, BAT 1 is the starting battery and BAT 2 is the house or accessory battery and it should be a deep cycle. You can start the engine on BAT 1, BAT 2 or BOTH but you would typically start on BAT 1. When the engine is running, switch to BOTH so the engine charging system can charge both batteries. If you leave the switch on BAT 1 or BAT 2, only the selected battery will be charged. So underway, use BOTH. When you anchor or when the engine is off during the day of play, switch to BAT 2. All of the accessories will then be powered ONLY by BAT 2 so BAT is protected and won't be discharged. When you are ready to go, its back to BAT 1 to start, and BOTH while underway. If you drew down BAT 2 a fair amount you could even run on BAT 2 to more quickly bring it back to full charge. How long that takes depends on the output of your alternator.
