GivEnergy Batteries Stuck in Calibration Mode (Stage 6) – Solved

I just wanted to reach out and say thank you to the community (and especially @Rubikcube) for helping me resolve an issue.

I have a GIV-HY5.0 Gen 1 inverter with 2 × Gen 1 5.2 kWh batteries, normally controlled by Predbat in Home Assistant. Last week, on a cold night, I noticed the SOC reporting 0% at around 1AM, even though the batteries should have been charging on IOG cheap rate.

Predbat appeared to be running correctly (I’d updated it the day before), but given the cold conditions I was concerned about leaving the batteries at 0% for an extended period. Battery temperature was ₁₇ °C, so I disabled Predbat and force-charged until 05:30, then switched the inverter back to ECO mode before heading to work.

Later that day, I checked again and found the system wasn’t behaving as expected:

• ECO mode on the inverter wasn’t discharging the batteries to cover house load
• Solar was working fine (covering load and charging batteries when possible)
• Manually scheduled battery charge/export still worked well enough to cover background house load
• When switched from read only mode, Predbat was reporting the system in calibration mode, so it wasn’t controlling anything

The only indication of a calibration event was a log entry saying “Battery SOC Calibration” in the inverter remote control logs.

I fully shut down and restarted the system, but no change. I considered manually starting a battery calibration, but with the cold weather I didn’t want to risk making things worse. My installer checked things remotely and suggested contacting GivEnergy support, suspecting a firmware issue or corruption (ticket raised, but I’m not holding my breath…).

Further reading on this forum led me to Rubikcubes app, (https://play.google.com/store/apps/details?id=uk.rubikcube.invertermonitor) which immediately showed the batteries were stuck at Stage 6 of calibration. That in turn led me to this post, which described exactly the same problem (albeit on an AC3 system):
Calibration Stuck

At this point I decided not to waste more time and bought the premium version of the app to try resetting the calibration. It didn’t work on the first few attempts, but I then noticed the system time was out of sync. After syncing the time and retrying the 'Stop Calibration' button, it worked immediately.

The system is now back in ECO mode, functioning correctly, and I’ve handed control back to Predbat. I’ll keep an eye on it, but everything looks normal again.

For me, the premium app was well worth the cost of a pint and a coffee to solve an issue that could easily crop up again. Huge thanks to Rubikcube for providing a tool that did what neither the inverter UI nor official support could (yet).

Cheers, mate 🍻

Gumby Well done for fixing it yourself, and thank you for supporting my app.

I am aware that the Stop Calibration and Sync Time functions can be a bit flakey. If they don't work first time, try again after a few seconds.

Be aware the the portal occasionally sends time sync messages to the inverter that aren't logged anywhere. I have only seen them in the early morning hours (shortly after midnight). If the hour is wrong, check that you have the correct Timezone set in the portal.

Unfortunately the "Random unscheduled calibrations" are a known feature of the Gen 1 and early AC3 systems. If it has happened once, it will happen again, could happen next week, more likely next year, it's unpredictable but at least now you know how to deal with it.