BMV 712 Current Vs Battery Current o MPPT

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bw32056 asked Sep 3, '20

BMV 712 Current Vs Battery Current o MPPT

Hoping to get explained the BMV readings and calculations. The MPPT is connected to a series of panels (2) and showing on the SmartSolar 100/30a MPPT a 5amp reading form the panels which are coming in at 43V and converting to the reading for the battery 13 V at the at 15Amp, I assume it is pushing 15amps into the battery minus the load

The BMV current reads exactly as the solar current output. I.E 5amps at 43V , shows 5amps at the battery ~13V, assuming it's normal but why shouldn't it show the Amps incoming in relation to the batteries voltage?

Does this then affect the "Consumed Ah" calculation if it is using the Current measurement of the BMV?

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Answer 1 · 2020-09-05T09:32:46Z

Paul B answered · Sep 05, 2020 at 09:32 AM

The BMV should be connected on the Battery side ONLY and should not be reading the solar panel volts at all only the MPPT reads those voltages.

the BMV reads the Battery volts and the Net current into or out of the battery

the MPPT units reads the battery voltage and the total amps going to the DC systems from the MPPT unit

the mppt also shows you the panel voltage and the panel amps. coming from the panels. Maybe if you could attach a wiring diagram of your setup if the above does not help you

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bw32056 commented · Sep 05, 2020 at 11:41 AM

Thanks Paul, yes the shunt is only connected tot the -ve battery terminal then to the DC load via a busbar. It isn't connected to the MPPT.

So if the MPPT is showing 18Amp on Battery side the BMV should calc approx 18amp - the DC draw/load.

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