What this order code actually is
The order code ACS550-U1-059A-2+B055 breaks down to a base of ACS550-U1-059A with a -2 suffix and a +B055 option code. The base name and option string are taken verbatim from the part number line. It sits in the Motor Drives subcategory, under Drives and the broader Motors & Motor Controls grouping, so it is sourced and quoted as a panel-mounted variable-frequency drive rather than a soft starter or a servo package. The only physical figure on file is a 9.07 kg unit weight — a chassis a single technician can lift onto a backplate, so panel handling is not the constraint here; the constraint is the voltage class and the option string the BOM was frozen against.
Family contrast — -2 vs -4 frames, and where ACH550 splits off
Inside the ACS550 line, the closest functional neighbor is the ACS550-U1-059A-4+B055. That part shares the 059A current frame and the +B055 option with this build, and ships at 36.29 kg per the peer row. Stepping up the current frame, the ACS550-U1-096A-4 keeps the same -4 voltage-class suffix and ships at 19.96 kg per the peer row. The ACH550-UH-023A-4 is a different product line — ACH rather than ACS, UH enclosure code rather than U1, 023A frame rather than 059A — so it is an HVAC-flavored ABB drive of related origin, not a same-frame alternate for this order code.
Sourcing posture
With no successor order code on file, quote this exact -2 / +B055 build against an RFQ rather than assuming a parametric alternate — the +B055 option string is what locks the BOM line.