The short answer
A one-off clears itself; if it repeats, log the times and insulation-test each PV string to ground.
Plain explanation
From the Huawei manual for the SUN2000 inverter: If it happens once, the inverter recovers automatically – just watch. If it repeats, record the times in FusionSolar. The rest of the checklist is below; work through it in order. Installer only: DC and AC work on a live PV system is dangerous, so owners should note the code and call their installer.
Steps from the source
- If it happens once, the inverter recovers automatically – just watch
- If it repeats, record the times in FusionSolar
- Installer checks the DC-to-ground insulation resistance of each PV string
- Repair the damaged cable/connector found
- Still active → vendor
Source
Huawei Inverter Alarm Reference, Issue 09 (2024-11-01), EDOC1100345192, Alarm 2051, §30, p34files.keno-energy.com ↗
Where installers ask this
- SUN2000 15KTL-M2 low insulation (r/solar)
- reddit.com/r/solar/comments/1lxgtc1/
- reddit.com/r/solar/comments/1ellz9q/
- reddit.com/r/solar/comments/1vktn59/
- reddit.com/r/SolarPakistan/comments/1uhs26h/
General guidance based on the manufacturer's manual or the named source. Always follow the current manual for your exact model and your national code. DC and AC electrical work is for qualified installers only. Not affiliated with or endorsed by any brand named; trademarks belong to their owners.