Duel Battery Systems

Wato.
I only run Piranha on all of my ambulance fleet vehicles, and I have had 100% reliability since we instigated the system into all vehicles as a standard specification. In fact If you ask around most emergency services in Australia who run dual batteries run with Piranha. the system as far as i am concerned has not failed me.
Cheers 4 now
Ash

G'Day wato,
As a totally hopeless auto electrician I installed a Redarc on my hilux following the directions supplied.
Worked fine.

Cheers
HowardT

Wato, I have an 05 TD Hilux. I fitted a Piranha battery tray (from TJM). Fitted like a glove. I used a Cole Hersey solenoid (which has been good, but with my time again I'd probably fit a Redarc). I use AGM batteries. Have a 90 AH in engine bay, a 120 AH in the back under canopy and a 120 AH in the CT.
For info on AGMs this is a good start:
www.fridge-and-solar.net/agm.htm

wato35,

Although I also run a Piranha (DBS150) Isolator, the "brand name" is less important than the functionality.

A good Isolator keeps the primary and auxilary batteries electrically separated from each other. A flat battery will not impact to other and you can always start your car with the good one.

A dumb solenoid arrangement, whilst cheap, invites trouble should one of the batteries go "ballistic". This arrangement simply parallels the batteries together and a damaged, or flat battery will soon bugger the other one and then you will be up that familiar creek without both a paddle, or a workable battery to get you home.

The DBS series of Piranha Isolators are very good at what they are meant to do.

Redarc's are fine, cheap, simple and reliable.

Hi Wato
Have had the Redarc for about 3 years. No Problems. I run a 50 ltr Waeco fridge from it when I go out bush. 2nd Battery is a Delkor not sure of size. Was recommednded to me by Battery world because my 2nd battery is in the back of the hilux which is a bit rough.
One thing I do use was good cable and made sure connections were good.

Howard.

wato, do what the Ambulance do - use Electronic system, not a mechanical solenoid.

Of the two you have mentioned the Piranha is the way to go without doubt, it uses no battery power to run it whereby the Redarc uses battery power to hold the solenoid 'slug' closed against the internal spring pressure.

However I replaced the GF's Redarc (and Aux battery Grrr) last month with a Matson electronic system for ~$200 fully inclusive with all cables and lugs included.

Link: www.matson.com.au/product_frameset.html

As to batteries the facts are readily available every where:
a wet cell battery takes LONGER to charge than an AGM Deep Cycle battery
a wet cell battery can't be safely discharged as OFTEN as an AGM Deep Cycle battery
a wet cell battery can't be safely discharged as LOW as an AGM Deep Cycle battery

If you only need to run a fridge for a weekend away, any type of budget priced Cranking battery will do the job, but if you want the fridge to run for a week or two then only an AGM Deep Cycle will give you unachievable battery performance when compared to a "passenger" car wet cell Cranking battery.

It's a case of 'horses for courses' a cheap Cranking battery will do the job with manual human intervention for a shorter period of time, and an AGM battery system designed to work with your charging system will cost more but will last longer and run much more efficiently, so in the long term it works out better on the hip pocket and saves the hassles of warm beer.