I will be picking up my new Island Star caravan this week which only has 1 x 100ah battery and 1 x 120w solar panel. My question is I want to put 1 x 200w solar panel on the canopy roof of the ute charging 1 x 135ah agm in the ute tray joined by an anderson plug, this way i can leave the ute in the sun and the van under a shady tree.
After sundown CAN I disconnect the ute solar panel and plug the van and ute batteries together via anderson plug and 6b&s cable ?
I want to do it this way to keep weight in the ute and out of the van.
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Greet everyone as a friend, its up to them to prove you wrong.
As long as the batteries are the the same chemistry (specifically, the same voltage profiles - but rather than worry about what that means, just use same tech / chem like both / all AGM) and as close to the same other specs (make, age, etc), then you should be fine mixing capacities
Charging them both (while interconnected) at the same with two different controllers / regulators could easily lead to less-than-optimal charging - of course, you're talking about charging them separately, and then connecting the batteries together after dark...
Sadly, this is all very likely to start an unpleasant debate (about mixing batteries)...
Thanks for the feedback Matt , to follow from your closing statement I appreciate any imput and will decide for myself what information I act on , but all to often these calls for assistance end in personal attacks.
Regards Peter.
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Greet everyone as a friend, its up to them to prove you wrong.
I see no intrinsic problem doing what you propose. However you might get a large surge of current when you connect the plug, if the van battery is discharged and the ute battery is fully charged. You might like to take that into account for various reasons.
Yep agree with the above and toadd, my concern as well would be when the batteries are connected together, there will be a surge of power as they balance and these types of batteries can be damaged if that surge is too high.
Once and a while is going to happen, but you plan would involve doing it really often, and that might really shorten the life of the batteries.
No problem with what you want to do. The only way you would get any sort of current surge is if one or the other of the batteries was dead flat or was faulty In other circumstances the voltage differential between the two would be insufficient for much of a surge current NO way you could THAT damage either battery, provided you have polarity correct!
Quite a common practise with many set ups
What you are proposing is essentially NO DIFFERENT to what A VSR or ignition controlled relay does when it parallels the Crank battery & house batteries[ two banks.] Except IT then has the full alternator power as well.
It would be advisable to have a fuse at each battery end of the Pos connecting cable just in case a short to Neg/frame develops[fire prevention]
Fuse size to suit CABLE current rating
.Use a good heavy duty style of fuse
ps No need to disconnect the solar reg,,provided both sets of batteries have the same charging specs
.Mainly Max charge voltage & float voltage
-- Edited by oldtrack123 on Wednesday 17th of February 2016 01:35:30 PM
