Dual battery setup (100 series)

**mullett** · 30-06-2010, 01:15 AM

I've been asked to add an 'isolator switch' to a friends 100 series, so that if a battery dies, it can be cut out. It looks an awful lot like the dual battery system is factory-fitted, or dealer fitted at the least using a factory kit. LHS battery has the wire to the starter motor (and the fusebox etc), then a heavy wire runs across from that battery to the RHS battery positive, which is also connected directly to the alternator.

As far as i can make out, there's no system in place to monitor/disconnect a battery, so the best option is remove the terminal from both batteries, connect this all to the output side of a 3 way isolator switch (left, right, both), and connect one battery to each. The other option is a digital dual battery controller, but I've never used one/don't know if they're worth having. Any thoughts? I'm leaning to the digital one, because it won't allow the starting battery to be discharged by a fridge etc...

-RM

**ra_28** · 30-06-2010, 04:00 AM

Mate just wire in one of these redarc isloators. They work a treat i've been using one in my 80 series for years. Run all your accessories off the second battery and just you starter off the main, As soon as the second battery draws below 12.3v it splits the batteries so your main holds it charge. If you main battery for starting dies there is the option to mount a switch on the dash which pulls in the second battery for starting.

http://redarc.com.au/products-and-se...tery-isolators

Regards
Alex

**The Last Streetfighter** · 30-06-2010, 11:43 AM

Redarc smartstart. FTW. Too easy campese.

**Dropbear** · 30-06-2010, 09:04 PM

Dual batteries on 100 series turbo diesel are factory fit, in cold weather they need both batteries to crank the engine due to the high compression they have, if you fit an isolator make sure it still uses both batteries to crank. LHS (passenger) is the "main" battery so you can isolate the RHS (drivers) battery from the rest of the system.