Product Description:

The 22VM51-020-6 is a permanent-magnet DC servomotor manufactured by Pacific Scientific for the Low Inertia PMDC Servomotors series. This frame combines compact dimensions with a lightweight rotor so axes can accelerate and decelerate quickly. Intended for industrial motion systems, the unit converts direct-current power into regulated rotary output, and its integrated analog tachometer plus optical encoder return speed and position feedback to the drive for closed-loop control. The low-inertia design also helps reduce response lag during repeated start-stop cycles and short indexing moves.

With a bus supply of 24 VDC, the motor reaches a nominal shaft speed of 2225 RPM while drawing 2.2 A RMS. Under that operating point, it delivers a continuous torque of 0.0918 N·m, which is consistent with a torque constant of 5.3 oz-in/A; each ampere of armature current produces about five ounce-inches of torque. These electrical and mechanical ratings indicate the steady-state load the motor can drive without exceeding thermal limits. Because speed in a PMDC machine is nearly proportional to applied voltage after normal losses are considered, limiting average current to the listed value helps maintain the published torque, while voltage regulation near the rated level helps stabilize commanded speed.

For transient demands, the winding tolerates up to 13.4 A maximum, allowing brief accelerations above the continuous operating range. Dynamic response is influenced by the back-EMF constant of 0.0374 V·s/rad, which represents the voltage generated per radian per second and must be considered when regenerative energy is handled by the drive. Armature impedance is low, with only 3.8 Ω of terminal resistance in series with a rotor inductance of 0.0006 H, so current rises quickly when the command changes. The tachometer voltage constant of 0.0286 V·s/rad provides an analog feedback signal, and the encoder’s digital pulses complement that signal for precise position verification during fine positioning tasks.