What it is and where it sits
The ABB ACS800-04-0260-3+P901 is an ACS800-04 series AC drive in the wall-mount / cabinet-build frame, listed under Drives / Motor Drives in the ABB low-voltage drives line. The order code ACS800-04-0260-3+P901 is the full string a buyer puts on the BOM and on the RFQ — the +P901 suffix is part of the configured code, not a marketing add-on.
Class context
This class of drive is used to run induction and permanent-magnet motors on industrial machinery, where the wall-mount ACS800-04 frame is the cabinet-build variant of the ACS800 family. Within ABB's drives lineup the ACS800 family preceded the current ACS880 platform; an ACS880-01 in a comparable current class is a different frame with a different footprint, so it is not a board-swap for a panel designed around the ACS800-04.
Sourcing posture
The ACS800 family has been superseded by the ACS880 platform. The configured code ACS800-04-0260-3+P901 is sourced to order against an RFQ. For an OEM with this part already qualified on a BOM, confirm availability, lead time, and any last-time-buy window against the RFQ before scheduling a new build.