What it is and where it fits
The ABB ACS550-U1-017A-2 is a UL Type/NEMA 1 enclosed drive in the ACS550-U1 series, rated for three-phase 208-240 VAC at 50/60 Hz with a 16.7 A output and a 4 kW motor rating, which puts it on the small end of the family sized for fractional-to-low-horsepower industrial motors on 240 V three-phase supplies. Construction is listed for US installation and NEMA compliance, so the enclosure, gland plate pattern, and field wiring land in line with the expectations of a US panel builder rather than a CE-only cabinet. It sits in the ABB drives catalog under the broader Motor Drives class, not a specialty or HVAC-only variant.
Reading the headline rating
The 16.7 A / 4 kW output is the figure that actually drives motor pairing — a 4-pole induction motor up to roughly 4 kW is the natural fit, with the 208-240 V three-phase input dictating the supply feed from the MCC. The 50/60 Hz frequency range covers both 60 Hz North American service and 50 Hz export applications without a parameter change. Because the enclosure is UL Type/NEMA 1, the drive is intended for a clean, indoor panel environment — wall- or panel-mount inside a control room — rather than a washdown or outdoor location, so any IP54 or outdoor application has to derate the enclosure choice upward before this drive is specified.
Handling and panel layout
At 5.67 kgs, the unit is light enough for a single technician to lift into place during panel build or field swap-in, and the weight is small enough that standard DIN-rail-style mounting hardware in the surrounding cabinet is sufficient without extra bracing. The NEMA 1 enclosure and US-installation construction mean conduit entries land on the standard US knock-out pattern, so a panel wired for the 240 V three-phase feed can accept the drive without reworking the gland plate.
Sourcing posture
The ACS550-U1-017A-2 is specified into the BOM as a quoted-to-order drive: the part code carries the exact output rating, enclosure, and regional construction the panel is being built around, so a buyer committing the line should quote against the full code rather than a generic 4 kW substitute. A same-series 240 V sibling exists at the 30 kW frame for designs that need to scale up within the same platform; for any other cross-reference, the part must be re-validated against the motor nameplate rather than treated as a drop-in.