hey guys my mech installed a solar panel and 20 amp redarc charger that’s only charging my crank and doing it well. But twin batt setup when isolated the fridge draws from crank if unisolated it’s drawing both batts which doesn’t seem right. If u disconnect the crank yes it’s drawing from aux IS THIS CORRECT? I thought it should draw from aux only and if so I don’t know how to fix it outlet is the rear constant one in the 100 series
Twin battery prob
- Thread starter luvsitwet
- Start date
The redarc charger input should be connected to your crank battery and alternator and positioned as close as possible to your axillary battery. The output of the redarc should be connected to your axillary battery. When the car is not running the redarc should be off and isolate both batteries from each other. Turn the car on and the redarc connects the axillary to the alternator to be charged. Providing it has been setup correctly.
In your first sentence your saying the redarc is charging your crank battery. The crank battery should be charged via the alternator. The solar panel should be connected to the redarc solar input and only charge the axillary battery. If the fridge is connected to the axillary battery it will run from both batteries, to a degree as both are connected together, when the engine is running and the axillary battery only when the engine is off. The isolation is controlled by the redarc charger. Sounds like something is wired wrong.
More info on the model charger you installed would be good.
In your first sentence your saying the redarc is charging your crank battery. The crank battery should be charged via the alternator. The solar panel should be connected to the redarc solar input and only charge the axillary battery. If the fridge is connected to the axillary battery it will run from both batteries, to a degree as both are connected together, when the engine is running and the axillary battery only when the engine is off. The isolation is controlled by the redarc charger. Sounds like something is wired wrong.
More info on the model charger you installed would be good.
Yes I agree but I think he did it other way around and by eye I can’t tell ime a tricky not a Leo but reasonable 12 v savvy how can I check as I’ve asked my other mechanic and the install guy and they all want the car for hours sounding like a 300 dollar bill for me. lol we’re and how would I connect my multi to check
Try disconnecting your axillary battery to the charger from the battery terminals. With the car off check the input terminal voltage, should have 12v, provided those cables go from the crank straight to the redarc. Taking he ran twin core cable. If nothing there check the output terminals. If you have 12v there it's the wrong way round. Also check the solar input without panels connected, disconnect at the solar panel if they are connected. Should have no volts there.
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bzykac
New Member
You need
REDARC SBI12 Battery Isolator 12 Volt 100A - Dual Battery - 4wd Battery Isolator installed between two batteries.
When voltage go up ( when you start up you car) more then 11.7V, REDARC will join two batteries together, and start charging both of them.
When you stop your car it will take power from both batteries, until voltage drop to (I think 11.7V) then it will disconnect and will drain only aux battery. Fridge and other accessories has to be connected to AUX batteries.
Never use mechanic to fix electrical issue.
REDARC SBI12 Battery Isolator 12 Volt 100A - Dual Battery - 4wd Battery Isolator installed between two batteries.
When voltage go up ( when you start up you car) more then 11.7V, REDARC will join two batteries together, and start charging both of them.
When you stop your car it will take power from both batteries, until voltage drop to (I think 11.7V) then it will disconnect and will drain only aux battery. Fridge and other accessories has to be connected to AUX batteries.
Never use mechanic to fix electrical issue.
Triton14
Well-Known Member
Welcome to the forum.
When posting it helps to be a bit more specific like giving us the exact model of the charger, the car its fitted to & possibly add some pictures.
You will get a quicker & more accurate answer that way!
I presume the charger is a BCDC1220 then??
The 1st thing I would do is check how the "mechanic" not the "auto electrician" has wired in the device against Redarcs own wiring diagram-
https://cdn.intelligencebank.com/au/share/yE9N/zJpl/A9Mo8/original/BCDC1220%28-IGN%29+Manual+English
Good luck sorting it out.
Triton14
Well-Known Member
My set up is pretty much this with the SB112 as per the threads in my signature + 1500W inverter.
Although I have earthed my ground for the AUX to the chassis to have some coin a a couple of meters of cable back to the starter.
Hasn't faltered.
Never had to use the momentary switch yet back to the starter yet if it was to fail, the Optima Yellowtop has been again faultless to me but its only 4 or so years old.
When the AGM packs it in I will be changing over to lithium DC-DC charger & a Kings 120AH LifePO4 making the SB112 & the Victron redundant but will be used for something else again one day.