Dual battery solenoid activation delay device?

hi moose,REDARC have a solenoid that does this, you can go direct or repco sell them they are a lot cheaper than the piranah ones. cheers rob

Yep, my Redarc does that , and very well to.

The other guys are right. Also you can install a push button switch so that it will engage the solenoid when pressed which connects the aux and starting batts together so you can give your starting batt a boost if need be.

Leroy

You can get a simple timing circuit kit from DSE or Jaycar but why make it hard for yourself. Use the ground from the oil pressure switch to activate the solenoid. If the engines not running then no ground to the relay and the batts are disconnectedI may be mad but I'm not crazy
BEAM ME UP SCOTTY

Hooroo
Ray

If you have a landcruser the aux terminal front lhs under bonnet disconects when cranking
cheers

MDM
4 treminals in little black box
Earth,
ACC (10AMP FUSED) OFF WHEN CRANKING
IG (10AMP FUSED) ON WHEN CRANKING WHEN EVER KEY IS ON
+B (20AMP FUSED) ON WHEN ALL THE TIME
Cheers Mac

The system I use is with a manual switch, but also through the windscreen motor power wire. So, the solenoid will definitely cut power when the ignition is off. When I switch the ignition to "ON", I have a choice (via a switch) as to whether I want the 2nd battery to assist with cranking or not. It is useful to be able to do this on really cold mornings. However, if the fridge has been running for a while and aux batt is low, then I leave the solenoid isolated to avoid the possibility of the 2 batteries linking when number 2 is very low and I may not have the CCA to turn the 4.2T/D over. I have a voltmeter mounted on my GU's dashpod with a switch below it. Flick the switch to the right to see # 1 battery status; to the left to check # 2. I always start my truck and allow at least 1 minute before driving off every morning. During that time I can watch the status of battery #1 come up to around 14v before switching the solenoid on to charge # 2. I also use this minute to pump air up on my receiver tank (for roof rack-mounted air horns and diff lock etc). It's just a little ritual I go through (a bit like a plane's pilot) every day to assist the longevity of my motor.
Cheers
Roachie

Moose, the timer was sold by the 12volt shop a few years ago here in WA. I had one in my old LC and it worked great. It delayed activating the solenoid by approx 3 minutes which allowed a bit of charge to go back into the main battery first. Before I installed it I went through a soleniod every 6 months. I was told they were installed to all Telstra 4x4's with dual batery setups. Simple and cheap but now they only want to sell the expensive electronically controlled soleniods. I'm looking for another delay timer myself but I guess I'll have to make up my own. Cheers
Allan

Moose. Mine does what you are looking for. Just remind me to demonstrate it!
cheers haze

Moose
Here's how I've done the job on my diesel landcruiser,
1. the wire which activates the solenoid is live when the key is ON (ie normal driving)
2. install 2 relays in this wire, configure them to work in the normally closed mode using the 87a terminal. This means that when power is applied to the relay, it opens or turns off.
3. switch one of these relays from the glow plug circuit , and the other from the starter solenoid.

All of this means that the 2 batteries are isolated from each other; when the glow plug circuit is live (this is on a timer and will vary depending on the ambient temperature and the engine temperature) and also when the starter motor is in operation - or both.

This system is simple, cheap and it works ok. Using the oil pressure switch (as noted above) is another option.

Over the years I've tried various methods of wiring up an aux battery with varying degrees of success. FYI I list these below.
a) Use 1 huge size truck battery to do everything (start ute & run auxillaries) - simple, heavy, hard to mount, expensive, worked ok on petrol engined ute.
b) Hella solid state battery isolater - simple enough & provided isolation between the 2 batteries , but dropped about 0.8 v from input to output - not a problem IF your alternator has an external, adjustable voltage regulator - just crank it up a bit.
c) Cole Hersey battery switch - was already installed when I bought the ute - worked sort of ok, used lots of battery cable resulting in voltage drop, relied on my memory to operate it !!
d) ElectronicsAustralis battery isolater kit - looked impressive with flashing leds but didn't work as required on a long trip away, not sure why , I just binned it and used method e)
e) a wire link between the 2 batteries - a tempory measure which worked ok but isolation required the remembering to remove/ replace the link each night/morning.
f) solenoid between the 2 batteries - the same electrically as e) but controlled via the ignition key, furthur refined by the addition of the 2 relays as detailed above.

I hope above ramblings are of some use to you, and others.

Cheers , Brownie