Solar Controller and Batteries.

[OXY]

This is a question aimed at Allan of aandncaravan really. My leisure batteries have been getting weeker and have finally given up the ghost, down to Seven volts not holding a charge. I have made some investigation into the solar set up and have found what seems a bodged DIY job. I have temporarily disconnected the panels.

I have Two small and one large solar panel, not sure of the size but the two small ones are linked together and go into one 10amp controller I found hid behind a panel, and the single solar panel goes into another 10 amp controller. Both the panel sets put out 20 volts. The out put side of both controllers are linked together, then a supply comes out of one of the controllers and then goes through a Fox D1 display and then straight into the switch supply of the Zig controll panel. Obviously this hasn't been working efficiently. I plan to rewire the whole thing and get a decent 20amp duel controller and go straight to the batteries. I also have a Van master connecting the leisure batteries to the engine battery. My only problem is that the solar panel cables come in through the roof at the back, and the batteries are under the drivers seat. Also I would like to get some better bigger batteries as the existing ones are 85 AH, but the space will only allow about 320mm Wide by 190mm tall. What would you recommend.

[aandncaravan]

That is a complicated set-up as not only do you have different sizes, but probably different ages of panels.

I am guessing that the use of two regulators has been employed to reduce the risk of the panels working against each other?

But that might introduce complications with one solar charger interfering with the operation of the other.

 

 

We haven't done solar for some time so can't really advise without being able to see it in great detail.

 

 

Reading between the lines I assume that you believe the solar is the issue for wrecking the batteries. If that is the case, it is likely to be through long term over charge, solely from the solar regulators charging the batteries when they are 'full'. That is generally a 'feature' of Solar rather than some 'fault', it just needs managing.

 

So the solution might be as simple as just isolating the Solar panels from the regulators when the batteries don't need charging.

See : http://www.aandncaravanservices.co.uk/ehu-full-time-yes-or-no.php

 

 

I think your best approach is to fit new Varta LFD75's, or whatever fits, then analyse in detail what you have and go from there. Find out what works well and what doesn't before you even think about starting to formulate a solution.

 

 

 

 

 

[OXY]

Thanks for the reply, but what about the way they are wired, by going straight into system and not to the Batteries ?

[aandncaravan]

Many motorhome Electronics manufacturers make provision for the power to go from the Solar charger to the Power Controller/distribution unit. Without knowing what solution you have and how it is wired, I can't comment on if that is good or bad.

Generally it is the best option but that assumes you are using the term Zig as a generic term rather than the actual manufacturer.