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Battery Monitor SOC Showing Empty Following Brief High Load

So, I've got a tiny little setup that has been going without issue for the past month. 100 Ah Battle Born, 150/35 SmartSolar MPPT, 712 Monitor, and an AIMS 2500W inverter.

I've been wanting to use the inverter to run my well pump to fill an indoor water tank. This takes only 7 or 8 minutes and even with my tiny battery bank and my less-than-efficient pump, the math shows this to be very much much within the limits of the system. I did a short, 3 minute test today to see what the actual load would look like and after doing so, my monitor is acting like I've completely drained my battery. The battery symbol in the lower right flashes and is hollowed out and the SOC percentage shows only a pair of dashes. The pump was averaging around 1300W according to the 712 for the 3 minutes it was turned on, which should only amount to a total draw of 65ish watts. What is more, the voltage shown by both the MPPT and the 712 after continues to show around 13.27V - clearly not an empty battery.

I've used the inverter on smaller loads before with no problem. I'm guessing that when the charge controller pops into float tomorrow the 712 will synchronize itself and all will be good, but I'd obviously like to not lose my monitoring every few days.

Is this a matter of improper settings on my end? A known glitch? Bad math?


BMV Battery Monitor
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2 Answers
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lehrling answered ·

Keep in mind that synchronization can be done manually also when you are sure battery is fully charged. (BMV can be set so it can never auto sync first)

Some may disagree with this, but it does remove the possibility of auto sync getting fooled.

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lehrling answered ·

Has the BMV ever been properly synchronized and current calibrated?

Do you have an inductive ammeter to measure the load?

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I can't say it has, no. It has self-synchronized at 100%, but I'm guessing that does little to nothing in regards to calibration of current. I have a multimeter but have not checked loads manually. The most I've done was to check the load on devices used on my previous setup vs this one.

Just looked up the process of zeroing the current and I may not have done that when I set it up. I'll do it tomorrow.