I have a smart lithium battery and 100/30 mppt, 500 wott pannle and dc to dc charger. My. Mppt also gose off bulk charge and moves to asbestos / float before my battery even reaches 50% is there reason why?
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Your MPPT is getting up to the absorption voltage of 14.2V. As your battery is not getting to 100% I expect that you have a high resistance connection between your battery and the MPPT due to the cables being too long or too thin or having a loose connection or you are using the cheap no name thermal breakers that do not work well. Use a multimeter on volts setting when you are charging to check the voltage at each location. Poor connection could be in positive or negative.
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The SOC on the Fogstar BMS is not the best.
It ignores currents under 1.5amps so I’m my case with only a 130w panel there is often a charge going in that just doesn’t register. Similarly my system has a quiescent current of 0.56amps which never registers. That’s 13.5Ah a day it never sees. As I have a smart shunt fitted I ignore the BMS and rely on the shunt
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Thanks guys that really helpful give me somewhere to go and look and have an investigation