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Ethan Steininger avatar image
Ethan Steininger asked

No solar current/wattage with MPPT, 12v isolated DC & BMV-712 on 2x 100AH BattleBp

6192aad4-6e17-4948-9094-1b1e550c5598.png48d8577b-187c-4fa0-afeb-04b5d9a1cbdb.png254dc594-70ff-415b-bc50-d568a90ac5bf.pnga147ddc3-b6e3-450e-ad87-bde86f896f84.pngb71f19f1-ceda-44f2-9a45-34355911af58.pngI’ve tried everything with troubleshooting this setup. I’ve got 2x 100 ah battle born lithium ion in parallel on a BMV shunt with an MPPT and DC/DC charger.

Screenshots of settings enclosed, I’m currently driving so the DC/DC charger which seems to work is putting batteries in absorption stage.

All my connections are rock solid and my batteries output the appropriate 12v power just fine.

BMV Battery MonitorMPPT SmartSolarLithium Batteryorion-tr smart
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Ethan Steininger avatar image Ethan Steininger commented ·

Does anybody have any thoughts here?

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2 Answers
Paul B avatar image
Paul B answered ·

Maybe its to do with the start charging voltage difference for MPPT as thats a min of 5v and maybe the panel voltage is to low and the charger you have may need 6 volts difference to start, anyway reconnect the 2 panels you have into a series config this will bump the voltage to 39volts and see if that helps


NOTE making the panels into a 38 volt array will not affect your charge voltage
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randy-putnam avatar image
randy-putnam answered ·

Looks like at the time of the screenshots your DC-DC charger was working fine and charging the BB’s. That being the case the MPPT senses it doesn’t need to charge the batteries. You’ve got the SOC set at 67%. The DC-DC will go to Float while you keep on driving, and if the batteries are not fully charged when you stop the engine the MPPT will take over until SOC is 100%. I think the MPPT and DC-DC are programmed to go Bulk-Absorption-Float whenever they are on. The Bulk and Absorption levels will be brief if the batteries are charged. Finally, why have you manually set the SOC at 67%? Seems you could set it at 100% or synchronize to 100% if your battery voltage is at 13.2 or higher when at rest. Finally, you can call BB and send them these screenshots. I have your same batteries on my boat and the folks at BB have been very helpful getting me through the Victron maze..

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