The short answer
Check meter-to-inverter wiring and SP-CT distance, then restart the inverter and SP-CT.
Plain explanation
From the Growatt manual for the SPH 3000-6000TL BL-UP: Installer checks meter-to-inverter wiring. Check SP-CT distance is within spec. 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
- Installer checks meter-to-inverter wiring
- Check SP-CT distance is within spec
- Restart the inverter and the SP-CT
Source
Growatt SPH 3000-6000TL BL-UP Installation & Operation Manual (Growatt doc, distributor-hosted), §9.2 Fault list, §9.2 Warning 401midsummerwholesale.co.uk ↗
Where installers ask this
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.