Battery’s / isolators and solar

[baggins]

Hi all in need of advise. I’m planing a new dual battery set up and I’ve got a few questions relating to different ways I’m thinking of set up. Any advise, experiences greatly appreciated.

Optima red top for under Bonnet use. Any heat issues?

Aluminium for battery tray is this a problem for battery’s?

Using different chemistry battery’s in dual system is it a no no..

Can I connect solar to the start battery via regulator and let my projecta isolator connect/and disconnect second battery. That is the opposite way most have it. Car sits for weeks at a time often.

Currently I use two N50 size battery’s under the bonnet with projecta isolator. Been like this for 8 ish years but I’m in need of a new battery and I’m adding solar so it’s time for a rethink


Thanks in advance

[aaron.miller]

I had a intervolt vsr connecting 2 batteries under the bonnet and wanted to add solar to top up the battery whilst I was at work. I purchased a 120w solar panel and a Gsl mppt regulator.
The car sat with the fridge running all weekend at home and then I connected the solar. After driving to work (20 mins) which only partly charged the batteries I let the solar do its thing. That afternoon I found that the battery hadn't charged very much and I noticed the solar was on float.
I spoke to the technical guys at Gsl and they advised that this is not what the regulator is supposed to do. They had designed the logic as once the panel gets some light on it put the unit into bulk charge. Then after either 4 hrs or it sees a battery full voltage then go into float and don't reset till it's night time and no charge is received from the panel.
So by driving the car you put the regulator into float early.
The only solution they could suggest was some sort of relay setup that might work.
I sold it and got a redarc bcdc 1225d, it expects to see the charge from both sources and seamlessly uses both sources.
Other mppt controllers may behave differently?

Aaron

[Sparky3975]

Hi all in need of advise. I’m planing a new dual battery set up and I’ve got a few questions relating to different ways I’m thinking of set up. Any advise, experiences greatly appreciated.

Optima red top for under Bonnet use. Any heat issues?

Aluminium for battery tray is this a problem for battery’s?

Using different chemistry battery’s in dual system is it a no no..

Can I connect solar to the start battery via regulator and let my projecta isolator connect/and disconnect second battery. That is the opposite way most have it. Car sits for weeks at a time often.

Currently I use two N50 size battery’s under the bonnet with projecta isolator. Been like this for 8 ish years but I’m in need of a new battery and I’m adding solar so it’s time for a rethink


Thanks in advance

Hi mate,

I'm not sure how the Project battery isolators work in regards to the isolation voltage or how you've wired it, but if it works similar to the Redarc SBI then it should work. There will be situations where you are charging both batteries together via the solar but it should be able to handle it. Is the reason for installing the solar on your starter battery purely to keep that topped up due to starting issues previously?