Dual batteries and solar question.

Hey fellas, just a quick question. Sorting out my dual battery setup so I can do some more extensive camping and not have to lug around a jump pack as a backup for my GQ.
I have fitted a kings dual battery VSR thing and have a 110w solar panel. I will be getting a 110ah agm battery minimum to sit in the rear cargo area where all my other auxiliary items will be charged (camera stuff/phones and camp lighting + fridge from time to time)

While at camp I will have the panel out to keep the aux battery topped up. Now my understanding of the VSR that I have fitted from Kings basically isolates the AUX and crank batteries when the engine (alternator) is off and the relay would only come on when it senses the crank battery is fully charged from the alternator.

What happens when I introduce charge from the solar panel into my Aux battery through my solar charger? Would the VSR sense this once the AUX battery has reached full charge and also start charging the crank battery (as in the reverse of what it is meant to do and is this going to be a problem?





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Not normally. If it's just a normal voltage controlled isolater it works of the voltage from the main (start) battery. If start battery goes over a certain voltage (13.1v?) It clicks in. If it drops below a certain voltage (12.5v?) It clicks out. Usually with a delay feature in there too.

That also doesn't mean it clicks in when your main batt is"fully charged" just when it shows a charging voltage.

Double post

Ok, I think that makes sense to me!
So running a solar panel through my controller onto the AUX battery shouldn't be an issue.

I am also wondering if my alternator is not performing as it should. I recently added a winch and put a multimeter on the battery as I was respooling it out of curiosity and noticed the volts drop to 12.1 when winching in with the engine rpm sitting at 1500 (rb30). I was only bumping the winch in button and max hold was for 5 seconds at a time as I was respooling the rope.
To me this doesn't seem right. I just can't remember how much is would drop on my old GQ TD42, same winch.
Also noticed massive drop when I flicked the old narva spot lights on. I've now ripped them off ready for some 9 inch LEDs to replace them with.
I am no auto elec but at idle the car reads 13.4-13.7 and when I flicked the spotties on it dropped and kept dropping down somewhere in the low 12's.

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No shouldn't be an issue charging your aux battery directly with your solar setup. Also, those voltages were just a guess so don't use them as gospel haha.

I'm no autoelec either but it sounds like your voltage should stay a bit more stable. Well above the low 12s. That's down in the isolator disconnect range. I.e.. your aux battery isn't going to get a charge at those voltages.

Thanks mate.
I will have to have a closer look and do a few more tests. Last thing I want it for my system to fail when I need it most (winching).

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As above I don't see a problem either way ,I run 120 watt solar fixed on mine but can join an extra 200 watt when overcast and rainy for extended periods which have so far gotten me through this trip without needing the gennie .
My advice is don't skimp on the solar controller go for a Victron mppt ,so far this trip it's meant the difference between needing the gennie and not .