dual battery troubles

[strut]

good afternoon iv been having trouble with a super cheep auto brand dual battery isolater,
it seems to run the main battery dead in over three days,
iv taken it back and exchanged it once already so im thinking it may be some other reason?
the second battery is always charged and when i disconnect the system the main battery is charged all the time
thanks for any advice

[sooty_10]

Supercheap auto isolator.......probably your problem right there. Unfortunately I'm not much more help. Sounds like it is drawing current from the main battery. Do you have access to an ammeter to measure the draw when it is all switched off?

Sent from my SM-G925I using Tapatalk

[strut]

yeah thanks, i was hesitant when i got it, i dont have a ammeter but i do have a multimeter if it can be used the same?

[macca]

Are you 100% sure the main battery has no load of it's own connected directly to it? If the isolator was connecting or not dis-connect then both batteries will be flat.

I am not familiar with the system you have, it could draw some current (amps) in the isolated mode which is not what you want.

A clip-on ammeter is fairly cheap at SCA and work well enough to indicate where current is flowing. Very handy tool to own.

http://www.supercheapauto.com.au/Product/SCA-Multimeter-Clamp-Mini-Digital/387596?menuFrom=1021627