Bowtie
06-11-2007, 02:17 PM
wtb battery isolator...
to hook up 2 extra batteries ... so lmk brand, price, trades?
TJElite
06-11-2007, 08:01 PM
What size isolator do you need? Do you want a true, diode based isolator, or are you looking for a relay type?
Lots of guys just hook all the batteries in parallel. While not the best plan, it works fairly well. Biggest downside is that you can drain all the batteries, and have nothing left to start the car.
A true diode isolator will keep them seperate, but also has disadvantages like voltage drop, and the batteries can not ever draw from each other.
The option I like best is a smart electrical switch. It senses voltage. As long as the primary battery voltage is greater than, say, 11.5v, the switch stays closed, and all batteries are essentially in parallel, giving you all the power. Once the voltage drops below 11.5, the switch opens, taking the load off of your primary battery, assuring that you can still start the car.
Whatever you do, make sure you fuse, or otherwise protect, both ends of the wire between the batteries.
Toby