Dual Battery Set up

**SnowMotion** · 04-02-2013, 12:07 PM

I am looking to install a second battery in my 2012 T5 Crew Van 132kw and am looking for some technical advise on the best set up.

I have read all about Split chargers with Isolators for the main battery and have now come across information about CAN-Bus equipped vehicles having variable output alternators. I have read the UK forums on this as well but all this information is leaving me unsure of exactly what I need.

My plan is the install a 100AH AGM battery under the passenger seat. This will have relatively light duties being used to run:
A cooler
Charge mobile phones
Charge computer if necessary
Maybe an inverter to run a heater
some lights

So the actual drain on a 100AH battery should be ok, my question is what is the method of charging the battery.

I have looked at 140Amp split charging systems that draw from the main battery with an low voltage isolator.
or
BC-DC battery charges like the RedArc BCDC1225LV, that is basically a battery charger drawing power from the main battery and amplifying to charge the AUX battery. This type also can run solar panels. (not doing this but maybe later)

If the 140Amp split charging system would work in the van I would prefer to go this way on a cost basis but my real question is would this work.

Any help on understanding how the battery/electrical/alternator system works would be appreciated.
I did a massive search on the weekend for this and really can not find an complete answer.

Cheers
Andy

**Transporter** · 04-02-2013, 12:18 PM

I have installed Projecta dc-dc charger in my 2005 T5 with 75AH Telecom battery and Projecta 1000W pure sinewave inverter. DC to DC charger works well with the deep cycle AGM batteries. There should be the thread with my install somewhere in the stickies.

**T5Pete** · 06-02-2013, 01:17 PM

i did a good install with a CTEK unit.

I have 2x55ah batteries installed in the rear in a box that i had around the wheel tub, one is permanently connected and one is hooked up in parallel with a mini anderson plug and is removable. I can hoy one out and use it camping, to run compressor if needed etc.

the ctek unit looks after the batteries, and can also take a solar panel in if required.

If you are in Sydney go and see Battery Business in warriewood (behind maccas). I went there, got all the bits, got a great price. we drew out what i wanted, test fitted batteries, he cut up and soldered and crimped every wire i needed to hook it all up and even lent me the hydraulic crimper to do the final crimp on the cable from the car battery to the ctek in the back. I even managed to hide the unit behind a magic panel in the right hand wall panel and have a pop off cover that hides the fuse box and ctek.

I've run my engel mt45 for 3 days with no probs. I also hooked up a ton of cig lighters and a dual usb power port in the back that is great.

pedro

**SnowMotion** · 06-02-2013, 07:24 PM

Thanks Pedro,

I work at Dee Why so not far to pop up to Warriewood and have a chat to them.
I have been leaning towards the CTEK 250S as it seem to do most things very well.

**Transporter** · 06-02-2013, 08:16 PM

Did you check the Redarc BCDC1240 ?

**SnowMotion** · 06-02-2013, 09:10 PM

Yes, had a look at the Redarc BCDC1225LV and spoke to the company and this is the unit they recommended for the van especially if I wanted to add solar power. The only downside is that it appears to be an additional $150 above the CTEK.
I have contacted an installer in the UK (who had good reviews) about what he is fitting to the T5's and he was very kind enough to have a look at my short list of items and he thought the CTEK was pretty much identical to what he is installing.

The only issue is just to finalize how much space I really have under the drivers seat (thinking of fitting seat swivel to passenger seat) to fit the battery, charger and fuse block. I will measure up a bit better tomorrow and see if I can make a decision.

**T5Pete** · 09-02-2013, 11:22 AM

I live in DY so if you want to have a look at mine give me a shout. I paid $300 for the ctek I think down from $500. its pretty smart so prob worth it.

oh yeah, don't limit yourself to thinking that batteries are all square, the place in warriewood has them in all shapes and sizes, hence i went with 2

**SnowMotion** · 04-03-2013, 08:07 PM

Originally Posted by T5Pete

I live in DY so if you want to have a look at mine give me a shout. I paid $300 for the ctek I think down from $500. its pretty smart so prob worth it.

oh yeah, don't limit yourself to thinking that batteries are all square, the place in warriewood has them in all shapes and sizes, hence i went with 2

Thanks for the offer Pete. I have been OS for a couple of weeks and now back into the project.
I ordered the CTEK 250S charger and also a 100ah battery. The charger has arrived and battery is due here this week.
I am mounting these under the drivers seat (provided I can get the battery to fit, pretty sure I can).
I ran the main power wire from the battery (not connected yet) to under the drivers seat. A very easy job with grommet through the fire wall and a good path under the floor mat.
The aim is to mount this up this weekend. I need to make a tray for the battery this week and a mounting plate for the charger.

**SnowMotion** · 09-03-2013, 08:07 PM

Managed to make up a cradle to fit under the drivers seat using the 4 mounting posts for this seat as the anchor points.
Fitting a 100ah battery is a very tight fit.
Had to relocate the module for the tow bar and fabricated a different mounting point.
I tried to fit the battery to the far right of the seat but found that the battery was too tall (even when on it's side) to clear the rails of the seat. Was only just not fitting (3mm), so needed to bend a couple of mounts to lower the battery and just managed to squeeze it in. The good thing in this process was that the battery would just fit in with the seat right forward and raised to the highest point so this made fitting easier.
I will post some pics in the next couple of days.