Logo
FULL SITE MENU

Battery isolation switch - why use one?

wynjim55

wynjim55

Regular Contributor
Is there a reason to use a battery isolation switch on small craft where only one battery is used for all purposes? Is there a need to have an isolator?








So far I haven't been on the water over night so running my start battery flat while out isn't a problem (I have upgraded all my old worn out halogen navigation lighting with LED units for if I get caught out) so don't see any need for a second battery. I have a switch I was going to fit to isolate all equipment when hooking up a mains power charger (refer separate thread).
 
A battery isolatator, depending on the model, can serve a number of functions. Even if you are only using one battery it could save your valuable electronics when starting your motor.

Some isolators will effectively switch "everything off" when power is being sent to the starter so in the event of a power spike you don't fry your expensive fish finder or gps unit.

If the isolator is the "discount automotive" type it probably does little more than separate two batteries - allowing both to charge from the alternator/stator while keeping the feeds to each battery separate - but (better) marine designed units will have features as I have noted above.

If you have a single battery with minimal connections and are essentially a day boater, then NO, an isolator would be of minimal to no value to you...
 
Not sure but i was told NEVER to switch the position of the handle from one battery to both or batt two while the motor was running that it could blow the stator in the motor.
 
Back
Top