Product Description:

The SMC-155 is a standalone stepper motor drive built by Kollmorgen for the SMC Motion Stepper Drives series. The unit converts low-voltage DC or bus power into precisely timed phase currents, letting industrial controllers position tables, dispensers, or light conveyors with open-loop accuracy. By integrating command, feedback, and power electronics in one slim package, it simplifies motion axes that require a compact footprint and repeatable incremental moves.

It operates in a microstepping control mode, dividing each full step into up to 256 micro-increments to reduce vibration and improve midrange smoothness. The power stage delivers up to 4 A of phase current, supporting medium-frame hybrid motors without external heat sinking. Regulation is handled by a bipolar chopper circuit that rapidly switches the supply voltage to maintain the commanded current setpoint. The drive is designed for two motor phases, and two encoder channels allow quadrature monitoring for position verification when a feedback motor is used. Four general-purpose inputs accommodate step, direction, enable, and homing signals, while the status port uses a push-pull output structure that can both source and sink logic-level current. Control, sensor, and power leads are separated across a 12-pin I/O header, a 4-pin motor plug, and a 3-pin power connector to streamline field wiring.

The aluminum enclosure is only 28.6 mm deep, 152.4 mm long, and 104.8 mm high, allowing high-density stacking inside shallow cabinets. Four molded mounting inserts align with #6-32 screws, and their threads match common panel hardware, so the drive can be fixed to a backplate or DIN adapter without additional brackets. A dedicated 4-pin motor connector keeps phase conductors close to the board traces and minimizes electromagnetic interference. The diagnostic output can sink 50 mA, enough to drive optocouplers or indicator lamps directly, while the three-pin power inlet supports quick disconnection during maintenance.