1x 16 kWh DO BAT DOCAN Energy battery connected to the CERBO GX via a Victron Type A cable, correctly recognised as recommended by the manufacturer
1x ET112 installed just before the main distribution board
1x EM112 at the injection point for the 6 kWh APS solar system
6 kWh of solar panels with an APS system
Everything works perfectly except when the battery is below 70% in the morning, from around 6 a.m. until 10:30 a.m. at the latest, during July–August 2026.
The message:
Instance 276
Device: VE-BUS System [276]
Description: “Low Battery Warning”, sometimes for a few seconds, then OK
I carried out a full check-up of the battery, with the logs sent directly to the engineer at DOCAN ENERGY. According to him, the battery is working perfectly!
70 mm² cable between the battery and the MULTIPLUS-II
AC in and AC OUT with 3 x 16 mm² cables
The whole system is earthed.
I’m looking for ideas to help me solve the problem
You need to look at the logs to try to see what’s happening.
Contact your distributor so they can analyse these logs and try to determine where the problem is coming from.
What are your values for “dynamic low voltage cut off” battery monitor in Ve.Configure of your MP2. I lowered all to 46V.
Did you compare the voltage measured by BMS and MP2? If they diff more than 0,2V under high load, I would check connections (clean with isopropanol, torque) or increase cable diameter.
1x16kWh battery might be a little small.
Please also check “dc voltage ripple” in advanced graph. Shall not be more than 0,2V.
After checking all the settings several times, and reviewing the logs with the battery manufacturer (Docan Energy), there was no battery anomaly.
Obviously, I checked all the wiring with an infrared thermometer, which showed a maximum of 26°C at each junction and on the cables — the same as the room temperature! No overheating!
Bjorn Kellermann’s message put me on the right track, and I no longer have any alerts; the SOC is now triggered properly.
I didn’t dare try it at 46V
The ESS Assistant values needed to be changed.
Attached are screenshots of my values before and after the changes.
