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BMS error
BMS errors may indicate numerous possible causes. Hence, it is important to ensure that
the batteries are under the right working conditions. The follow inspection is to be performed
before contacting Growatt.
1. The voltage level of the battery modules used. The operating voltage range of the
ARK 2.5H-A1 battery is 47.2 - 56.8V. If the battery is under or over voltage, it should
not be used anymore.
2. The voltage difference between each module should be less than 0.5V. If the voltage
difference is higher than 0.5V, the battery may cause errors.
3. Make sure that all connections are fastened. Change cable if necessary.
4. Install proper grounding in the installation. A potential difference between the BMS
and inverter can also cause problems.
5. If online monitoring is not available, a local Firmware update can be performed with
the appropriate files on a USB stick. Always contact Growatt before any update.
Failure to do so may cause damage to the system that is not covered under
warranty.
Difference in battery voltage or too deeply discharged batteries
If the difference between the module is too large, or if the batteries have dropped below 48V
but still, you can fortunately bring them back to normal by charging them with an external
battery charger.
When the module voltage different is too large, or battery voltage is between 36V and 48V, it
is possible to charge the battery back to working voltage range by using a lab DC charger
power supply. Charger should be set to constant voltage 52V with 5A current. Stop charging
when the current reduces to 0.5A.
Measure the voltage after letting the charged battery rest for 2-3 hours. Make sure that the
voltage between battery modules is the same, then place them together with the BMS and
inverter.
Very important: Pay attention to the polarity! Having the polarity inverted can blow up a lab
power supply.