Product Description:

The SS252B-2003U is a constant-speed synchronous motor produced by Danaher within the Slo-Syn Synchronous Motors series. In industrial automation, it supplies fixed-ratio rotary motion for indexing tables, mixers, or metering pumps that do not require variable-frequency drives. By locking its rotor to the applied line frequency, the unit offers predictable step accuracy and eliminates the need for external feedback devices in simple positioning tasks.

The motor is wound for a supply of 240 Vac and draws a steady 0.40 A under rated load, pairing easily with control transformers or solid-state relays sized for fractional-horsepower duty. When energized at 60 Hz, it turns at 72 rpm; operation at 50 Hz yields 60 rpm, allowing the same frame to serve installations with either frequency. A minimum running torque of 250 oz-in helps prevent process transients from stalling the shaft. The single-phase stator works with an external 330 Vac capacitor to develop a quadrature field, and connection is made through a terminal board that facilitates quick lead changes for clockwise or counterclockwise operation. Internal heat rise is moderate, so a 500-ohm resistor can be added in series for dynamic braking without exceeding the 50 W dissipation limit.

The shaft can accept an axial thrust of 50 lb and a radial side load of 25 lb, supporting direct mounting of sprockets or small pulleys. Inertia matching to downstream mechanisms is simplified because the rotor tolerates a maximum reflected inertia of 0.12 oz-in-s² at 60 Hz, reducing the risk of step loss during rapid starts. Overall mass is kept low at 8.0 lb, so the motor can be cantilever-mounted on light aluminum plates. Its single-phase topology cooperates with the capacitor and resistor to deliver smooth torque while minimizing the component count in compact machine panels.