What you're actually ordering
The ABB ACS800-U1-0020-2+P901 is a wall-mount AC drive on the ACS800-U1 family, carrying the +P901 option suffix on the order string.
Frame sizing and what that means for the panel
At 25.85 kg, this is a two-hand lift on the panel wall — the U1 family is the wall-mount series, so the cabinet has to be sized for surface mounting rather than DIN-rail capture, and the cooling clearances on the U1 frame drawings apply to this frame as well.
Sourcing posture for a contract build
For a contract line where the customer has ABB on the AVL, this code is specified into the BOM as-is — the +P901 suffix has to read identically on the nameplate against the purchase order, because that string is what the customer's incoming inspection and any deviation paperwork will trace back to. Where the customer permits an approved alternate, the ACS880-01 frame from the same vendor is a different firmware and control-panel footprint than the ACS800-U1 and would need an approved engineering change rather than a silent swap.
What we need from you on the RFQ
Send the full order string, the destination panel tag, and whether the +P901 option content has to match a specific firmware load — that is the single most common source of an AVL mismatch on this family. Compliance documentation (declaration pack, nameplate photo, country of origin) is bundled with the quote on request — flag that requirement at RFQ time so the paperwork lands with the unit instead of as a separate chase.