What this line is
The ABB ACS800-U1-0001-2+P901 is the 1HP frame of the ACS800-U1 wall-mount drive family, ordered with the +P901 option code appended to the base part number. The listing names ASEA BROWN BOVERI in the title field, reflecting the legacy brand line that ABB carries on the ACS800 series. The 1HP frame weighs 4.54 kgs, in the small-footprint wall-mount class. It handles low-horsepower motor control on standard industrial supplies.
Second-source against the ACS880-01 family
For a contract-build buyer weighing an approved alternate on the same BOM line, the ACS880-01-11A0-5 is the same 4.54 kgs weight class and the closest functional second-source — different firmware family, but same wall-mount footprint slot. Whether it drops in without rewiring is a panel-by-panel question: the ACS880 family is the ABB-recommended successor direction, but it is not a field swap for the ACS800-U1 line and needs a controls-engineering review before it goes onto a customer's AVL as an approved alternate.
Contract-manufacturing buyer view
On a contract line with three different end-clients, the ACS800-U1 base family is the older ABB platform, while the ACS880-01 line is the current production direction. Specifying the +P901 option into a BOM that references the ACS800-U1 series is on the customer's AVL only where that AVL still carries the ACS800 platform — a deviation request is required if the end-client's AML has moved to ACS880 only. The 1HP frame at 4.54 kgs stays a single-line entry; the swap question is firmware/option-code compatibility, not physical handling.