24V to 12V DC to DC charger, need some help with wiring to ignition.

[eliurquhart]

Hey Guys,

Im pretty amature with my wiring skills. I have purchased a 24 - 12 v DC to DC charger from Jaycar.
I am pretty keen to wire it in myself. I have my auto sparky crimping the heavier cabling for me and sorting that side so I can just connect all of that up. I was wondering though where I would get an ignition source from. I was wondering if I need to tap into the ignition from the wipers or some other accessory like that and if I do that do I need to access the key barrel or should I just find the ignition wire running off the wiper motor and splice into that?
If that is the case would I also need to have a fuse running from the wiper to the charger? there is an inbuilt fuse in the case already.
Anyhelp would be great.

:blowup:

[JoeG]

Hi I spliced into the wiper ignition live wire then put a inline fuse so I use that for all accessories that are ignition dependent (intercooler fan) DC/DC charger etc
Hope this helps
Regards
Joe

[chrisc2306]

Hi there what are you installing that is 12V? I have a safari and had to do this for my stereo and I tapped into the factory converter at first but that couldn't generate enough power and the stereo kept turning on and off so I ended up wiring from the left hand side battery as you look at the engine bay to the converter and picked up an ACC feed at the factory converter (blue wire). If you need anymore help I can give you some more info on how to wire it up

[eliurquhart]

Chris hows it bro? Im from Wanaka too classic, living in western Australia at the moment.
I am putting in a 24 - 12V batt charger so I can run the engel and a few other acc instead of constantly tapping off the crank Batts and find 24v gear. I have a redarc reducer already for stereo and a few other 12v gear and have spliced into the rear cigi socket for the fridge socket but would like to set up an Aux system to charge with Car and Solar, have got the batt (100Ah AGM from fusion and Batt charger from powertech) just need to set it up. I have all the cabling made up from the auto spark as its 50amp 6mm wire and they reckon solder and crimp which was an epic decision as its clean and solid and easy to maneuver. The diagram that I got was pretty straight forward but I dont know if I need 12 or 24v to switch the dc/dc on. there were no instructions in regards to this. I have 3mm cable for this so I guess 10amp or something like that and the charger has inbuilt fuse so guessing that I rely on that on.
My take is that basically I splice into the live wiper wire ( 12v reading on that one with the multi ) and run it direct to the DC/DC and can put a fuse in if need be. bobs your uncle? haha
Am i warm or cold?
cheers fellas

[GQ TANK]

Center tapping the crank battery, is the quickest way to kill the battery - Using the dc-dc invertor is the best approach.

The wiper wire is nor\t designed to handle the extra current that you will be running though it - (its probally being provided by the vehciles dc-dc invertor.

I would use the Wiper 12 Volts to actvate a heavy duty relay that will pprovide power to the invertor when the ignition is on.

Another way would be to use a redarc 24 volt dual battery isolater - as they only activate once the charge volts are at a defined level - ie the motor is running. then connect the redac to the dc dc invertor. The added bonus is that the redac has a arc suppressor - less chance of the dcdc invertor or other components being fired by a back emf from the relay switching - would be simpler to wire as well but a bit more costly.

[eliurquhart]

Hey Tank,

I used the wire from the wiper motor, its 3mm also, I only need a small kicker to get the charger working. I have the main lines from the Batt to charger to batt on 6mm with 40amp fuses in between each batt. I talked to my sparky who did all the crimping and connectors and he thought it would be sufficient. I have wired it up yesterday and works no worries. Do you think that there would be some issues in the future with this set up?
It has a few back up cut outs with it. for $300 youd hope it would be good

[chrisc2306]

Chris hows it bro? Im from Wanaka too classic, living in western Australia at the moment.
I am putting in a 24 - 12V batt charger so I can run the engel and a few other acc instead of constantly tapping off the crank Batts and find 24v gear. I have a redarc reducer already for stereo and a few other 12v gear and have spliced into the rear cigi socket for the fridge socket but would like to set up an Aux system to charge with Car and Solar, have got the batt (100Ah AGM from fusion and Batt charger from powertech) just need to set it up. I have all the cabling made up from the auto spark as its 50amp 6mm wire and they reckon solder and crimp which was an epic decision as its clean and solid and easy to maneuver. The diagram that I got was pretty straight forward but I dont know if I need 12 or 24v to switch the dc/dc on. there were no instructions in regards to this. I have 3mm cable for this so I guess 10amp or something like that and the charger has inbuilt fuse so guessing that I rely on that on.
My take is that basically I splice into the live wiper wire ( 12v reading on that one with the multi ) and run it direct to the DC/DC and can put a fuse in if need be. bobs your uncle? haha
Am i warm or cold?
cheers fellas

Nice one mate we should get a beer next time you're over! Maybe take my safari on a mission somewhere too! Glad to hear the install went well. If they are both 3mm I'd say you're pretty safe and with you having back up cut outs you should be sweet with that!