BMS Under Voltage Query

Hi, I'm still very new to all this...

I keep getting a BMS Under Voltage notification on my inverter notifications. Is this something I should be concerned about? Is it damaging my battery?

Only change recently is I signed up to Flux, and charge my battery between 0200-0500 and discharge my battery between 1600-1900. The battery is protected to not go below 4% thpugh.

Thanks (copy and paste from notifications below for reference)

BMS Under Voltage 2023-12-11 21:53:21 2023-12-11 22:03:35
BMS Under Voltage 2023-12-07 21:13:01 2023-12-07 21:23:15
BMS Under Voltage 2023-12-06 16:57:53 2023-12-06 17:08:46
BMS Under Voltage 2023-12-06 08:01:06 2023-12-06 08:16:27
BMS Under Voltage 2023-12-05 23:34:22 2023-12-05 23:54:51

Can you correlate these events with the historical battery state of charge at the time? Some people report sudden drops in SoC, and maybe you see similar at the same time.

It is hard to tell the true capacity of the battery while it is under load (discharging). It's possible that the system believes there is more than 4% available, but then finds the voltage lower than expected and stops abruptly.

Oh, what version of the firmware are you running?

Hi, thanks for the reply.

I'm on the latest firmware,
Inverter is a GIV-HY3.6
Inverter Firmware Version D0.393-A0.393
Last Update Time 2023-12-02 22:53:12
Battery Firmware Version 3015

I'll paste the SOC immediately below each BMS Under Voltage date/time:

BMS Under Voltage 2023-12-11 21:53:21
TIME 2023-12-11 21:53:21
BATTERY VOLTAGE 44.63V
BATTERY POWER 0W
BATTERY TEMPERATURE 15C
BATTERY PERCENTAGE 6%

BMS Under Voltage 2023-12-07 21:13:01
BATTERY VOLTAGE 44.58V
BATTERY POWER 0W
BATTERY TEMPERATURE 11C
BATTERY PERCENTAGE 11%

BMS Under Voltage 2023-12-06 16:57:53
BATTERY VOLTAGE 44.7V
BATTERY POWER 0W
BATTERY TEMPERATURE 1C
BATTERY PERCENTAGE 12%

BMS Under Voltage 2023-12-06 08:01:06
BATTERY VOLTAGE 44.71V
BATTERY POWER 0W
BATTERY TEMPERATURE 3C
BATTERY PERCENTAGE 7%

BMS Under Voltage 2023-12-05 23:34:22
BATTERY VOLTAGE 46.23V
BATTERY POWER -84W
BATTERY TEMPERATURE 11C
BATTERY PERCENTAGE 0%

I'd be VERY concerned indeed about voltages going down that far as it will be causing damage to the battery cells.

Get onto support ASAP.

Scottishcammy I'll paste the SOC immediately below each BMS Under Voltage date/time

The cloud only records snapshots every 5 minutes. Are these the results immediately before the notification, or immediately after? (Before is probably more useful.) I'd be looking at the trends on approach to the event timestamp: is the SoC smoothly heading towards 0, or does it jump at the end ?

it's interesting that a voltage of 46.23V corresponds to 0% (last event), but 44.58V corresponds to 11% (2023-12-07 21:13:01), at similar temperatures.

I don't quite get to the point of Low Voltage BMS errors on 3015 but I do get mighty close (~ 46V / ~ 4% battery actual)
For me it happens after it does it's SOC readjustments:
Goes down to 15% actual (4% Inverter reported SOC) and stops, within the hour (as expected) it reassesses the SOC level and usual gains 1-3%, where it discharges again for a little bit and stops again at 15% (4%) only this time, once it's stopped and reassess true SOC it decides that actually it's overcooked it and rescales back down to about 5% which gradually ebbs away until the nightly recharge occurs.
So I gain in capacity (should have 6.5kWh available) and actually get over 7 however this is to the detriment of the battery longevity so not without it's downsides.

hoggy 3015 is charging to the calibration limit (and beyond) here (more than 2 cells at 3.55V) unless I prevent it from doing so & I know I'm not the only one seeing overvoltage warnings either!

You have to wonder about the competence of whoever is coding this firmware. 3012 was a fail, 3013 was an unmitigated disaster which killed batteries, 3014/15 charges to calibration limits....