Customer question (received via email 1st July 2020):
I'm looking to keep batteries maintained in my T5 camper which gets fairly infrequent use. It has a 110A leisure battery and a cranking battery. I am assuming that solar is the best option. Side windows are tinted.
Willgen Reply (Email from Bill 2nd July 2020):
Many thanks for getting in touch. Your options are:
Option 1 - A solar charger for each battery.
I'd recommend two Optimate 10W solar chargers
. Slight problem is we have only one left in stock and do not know when new stock will arrive (Covid has interrupted supply chain unfortunately). You could go for an optimate 10 for the starting battery and an Optimate 20 for the leisure battery.
Option 2 - One solar charger shared between batteries (manually swap it over between batteries periodically).
Go for an Optimate 20
(or larger) solar charger and swap it between batteries as required.
Option 3 - One solar panel wired back to a dual charge controller which is connected to both batteries and will charge them simultaneously.
For battery maintenance when the van is parked up (assuming no large parasitic drains on battery) a 20W panel should be sufficient. If you want some extra power for charging the leisure battery when you are using the van use a larger panel (eg PV Logic Flexi 60W). You could go for a semi flexible or glass fronted panel. My preference for a van would normally be semi flexible. You can keep it in the cabin or permanently mount it outside if you prefer.
Note the wire looms are 2m long so if batteries are located in different locations a longer cable may be required for one of them ( I can make one up for you). The PV Logic flex 20W comes with 4m cable - so you may also need additional cable to run from the solar charger back to the charge controller. If you want to be able to connect/disconnect the panel I would suggest using MC3 connectors.
I hope that this helps. If you have any questions or would like to proceed with an order please get in touch or order on the website.