Freeze the exact product pair
Begin with the complete module and inverter model numbers, document revisions and proposed MPPT/string arrangement. A family datasheet can cover multiple power classes with different electrical values. Record the precise column used and keep a copy or link in the job evidence pack.
Voltage has two different jobs
The maximum-voltage check uses string open-circuit voltage corrected for the expected lowest cell temperature. Manufacturer instructions from LONGi and SMA both state that cold open-circuit voltage must remain within the relevant system and inverter limits. This is a hard equipment and safety boundary.
The operating check uses the module’s maximum-power voltage across expected operating temperatures and compares it with the inverter’s MPPT and starting ranges. Passing the maximum-voltage check does not prove that the string will track efficiently when hot, and sitting inside a broad operating range does not necessarily mean full rated power is available across it.
Current is more than one number
Record module operating current and short-circuit current, strings per MPPT, the inverter’s usable input-current and short-circuit limits, and any connector or input constraints in the product instructions. Parallel strings add current. Manufacturer terminology differs, so do not substitute “maximum input current” for a separately specified short-circuit-current boundary.
Check the physical and supported configuration
Confirm compatible connector families, conductor and protection design, earthing arrangement, module type restrictions, MPPT sharing rules and any optimizer or rapid-shutdown requirements. SMA’s product instructions, for example, distinguish electrical limits and state configuration expectations for modules sharing an input. The exact product manual wins.
Use Wattbench as a worksheet, not approval
The compatibility worksheet compares the values you enter and the string sizing calculator exposes its temperature formula. Neither knows every product restriction or the current standard. Save the result with the source documents and have the final design completed by the appropriately licensed and accredited person.