Record what was removed and why
Before replacing equipment, capture the failed inverter’s exact model, serial number, firmware if accessible, fault history and connected PV strings, battery, meters and gateways. Note whether the replacement is warranty-equivalent, a manufacturer-approved successor or a redesign. This prevents a future technician from assuming the new inverter has the same limits as the old one.
Revalidate the PV inputs
A replacement inverter can have different MPPT voltage windows, input-current limits or permitted parallel-string arrangements. Recheck each string rather than transferring cables by position alone. Confirm polarity, insulation results, expected open-circuit voltage and current, and map each string to the intended MPPT. Use the MPPT voltage and current guide where the input design has changed.
Recheck battery and backup compatibility
For hybrid systems, confirm the exact battery remains on the approved list for the replacement model and firmware. Validate communications, state-of-charge reporting, charge/discharge limits, transfer hardware and backed-up circuits. A replacement inverter that can operate PV correctly may still need additional configuration before storage and backup operate correctly. Review the battery and firmware checklist.
Restore grid and protection settings deliberately
Record the country/grid profile, export limit, protection thresholds, meter orientation and any distribution-network settings. Do not assume a factory default matches the previous approved connection. If the local utility or network operator requires a replacement notification, test certificate or new settings evidence, include it in the handover file.
Reconnect monitoring ownership
Verify the owner’s monitoring account, site name, gateway association and installer access. Check that production data is updating and that battery, meter and consumption channels have sensible signs and values. Preserve the old monitoring record where possible instead of creating an unexplained duplicate site.
Close with a reproducible handover
Store photographs, serial numbers, firmware versions, commissioning test results, revised single-line diagram and the reason for replacement. The system commissioning and handover checklist can be used as the final cross-check so the repair remains understandable years later.