Solar - two battery banks.

[Traveller]

Have a solar installation where the controller can handle two battery banks, but only if those banks are never joined. Mine are joined when I switch the 1,2, both switch to both (when charging via the engine) so I cannot use the two bank capability. I currently have the solar charging the domestic bank only. I appreciate that I could have it charge all batteries when the switch is on “both” as it would see them as a single bank but this won’t work when I am away from the boat (not a live-aboard) as I like to leave the isolation switch in the off position. Thus when away my starter battery is not benefiting from solar.

Above has not been a problem so far but is there a way around this limitation? It may well be the best option is to live with what I have but it does seem a bit of a waste

[Boredrider]

A fairly expensive but fully automatic solution is to use a Smartguage/Smartbank setup. A large relay would replace your 1,2,both switch. As soon as a charging source (alternator, solar, or battery charger) is detected, the smartbank will connect batteries together in one bank. The Smartguage will give you accurate information about the remaining capacity in the domestic bank. Pretty much fit and forget in my experience.

[OldGoat]

The engine start battery doesn't need a lot of charging between trips 9providing it's not clapped out), so may not be worth the hassle of expensive switchgear?

[Traveller]

The engine start battery doesn't need a lot of charging between trips 9providing it's not clapped out), so may not be worth the hassle of expensive switchgear?

Fair point.

[Phil Ambrose]

Or do what I did, bought a £20-00 20watt panel dedicated to the starter battery, found it on eBay.

Phil

[Arthur Brown]

A small separate system for the starter battery would work well for you.

[Traveller]

Thanks all. Food for thought there.

[Top cat]

I use a small (24w) solar panel to keep my starter battery topped up and a larger one for recharging the domestic batteries, works well.

 

Top Cat

[Traveller]

I shall probably go that way TC. Just seems a waste of a dual bank controller, but it works well enough on one bank only :-)

Edited September 7, 2015 by Traveller