dual battery w/isolator and solar charging

[496bb]

So, looking to put in two fresh batteries and make a dual setup. I have a diode isolator. But, I see these Cyrix isolators, and I'm trying to figure out how I could wire in a simple cheap solar trickle charger to keep both batteries topped off, as this won't be a daily driver. Anyone done this?

 

[Ricko1966]

So, looking to put in two fresh batteries and make a dual setup. I have a diode isolator. But, I see these Cyrix isolators, and I'm trying to figure out how I could wire in a simple cheap solar trickle charger to keep both batteries topped off, as this won't be a daily driver. Anyone done this?

Maybe make your life easy. New Volkswagons used to ship with a solar battery maintainer installed,so dealers never had a dead car on the lot. Dealers removed them before sales. They suction cupped to a window and plugged into a cigarette lighter,dealer techs used to peddle them on ebay for 10.00 I bought one there but it's been years. Maybe still a thing,maybe not but easy to check. Just looked on ebay not cheap anymore I snapped you 2 screenshot 1 so you'd have specs.

 

[Grit dog]

^Great piece of trivia or memorabilia but there’s so much out there for solar maintainers compared to whenever VW did that it would imo make sense to use some “new” solar.

So, looking to put in two fresh batteries and make a dual setup. I have a diode isolator. But, I see these Cyrix isolators, and I'm trying to figure out how I could wire in a simple cheap solar trickle charger to keep both batteries topped off, as this won't be a daily driver. Anyone done this?

Considering most of the retailers for the Cyrix also post the installation instructions, I’d just follow those.
If you are installing new, yeah ditch the old diode isolators idea. They still sell em, but why…there has been better technology for quite a while now.
The bigger question is why the isolator? Are you using the batteries as a house/start battery combo or just want the additional battery capacity in general? If the latter then just run batteries in parallel and hook the charger to the most convenient one.
If the former, same thing. Install the isolator/combiner and run the charger to the most convenient one. Same goes for the alternator. Any auto charging relay will work both directions.
I’ve had one on my boat for a lot of years. It’s simple and easy and reliable. (I have a blue sea brand but it’s similar to the Cyrix you posted)

 

[Ricko1966]

^Great piece of trivia or memorabilia but there’s so much out there for solar maintainers compared to whenever VW did that it would imo make sense to use some “new” solar.

Considering most of the retailers for the Cyrix also post the installation instructions, I’d just follow those.
If you are installing new, yeah ditch the old diode isolators idea. They still sell em, but why…there has been better technology for quite a while now.
The bigger question is why the isolator? Are you using the batteries as a house/start battery combo or just want the additional battery capacity in general? If the latter then just run batteries in parallel and hook the charger to the most convenient one.
If the former, same thing. Install the isolator/combiner and run the charger to the most convenient one. Same goes for the alternator. Any auto charging relay will work both directions.
I’ve had one on my boat for a lot of years. It’s simple and easy and reliable. (I have a blue sea brand but it’s similar to the Cyrix you posted)

Has Solar really changed that much since the TDI golfs?

 

[496bb]

Grit,
I looked and I actually have a PAC200 - which actually just connects the two bat + so basically parallel. My concern is that my research indicates this means both batteries will equalize and constantly do so, so they will wear down prematurely.

Old theory is both batteries need to be the same age,CCA, etc - but with the newer Cyrix type intelligent isolators it seems like maybe they can be completely different.

My use would be having the aux batt for camping, off grid power needs, and tailgating type stuff. Current battery is bad so if I need them to be the same, need to buy two now - otherwise I could just do the one and add a second later if the newer isolator technology keeps em separated better.

 

[Ricko1966]

@496bb don't know why this just clicked in my head, you could use a 4 wire trailer plug,two wires connected to 1 battery 2 to the other battery. Another 4 wire connector,2 wires to one solar panel 2 to another. The 4 wire wire plug would keep polarity from being switched 1 plug, plugs in 2 small panels,and charges both batteries independently. Assuming both batteries are isolated when parked.

 

[496bb]

hmmmm, interesting idea