Product Description:

The 55NM82-000-2 is a permanent-magnet DC servomotor produced by Pacific Scientific and supplied within the Low Inertia PMDC Servomotors series. Designed for closed-loop velocity or position control, the unit converts electrical power into mechanical rotation for indexing tables, pick-and-place axes, or small actuators where rapid acceleration and tight settling times are required in industrial automation. Its low rotor inertia helps machines change speed quickly, while the brushed construction simplifies drive electronics when compared with AC servo alternatives.

It operates from a nominal supply of 36 V and draws a continuous armature current of 10.9 A (rms) when producing its rated output. Under those conditions, the shaft delivers 1.667 Nm of torque at a regulated 1495 RPM, corresponding to a mechanical power output of 261 W. The terminal resistance at 25 °C is 0.65 Ω, and the rotor inductance is 225 µH, while the torque constant of 0.1695 Nm/A links commanded current directly to motor torque for accurate control. Internally, copper losses are limited by a 130 W power dissipation rating, and the armature circuit responds to voltage steps within an electrical time constant of 0.35 ms; the rotor reaches 63% of final speed after a mechanical time constant of 1.6 ms. No-load velocity tops out at 1980 RPM, giving headroom for speed regulation.

During fast indexing or emergency stop events, the drive can inject a momentary 55 A pulse to overcome load inertia without exceeding thermal limits, and the armature withstands a stall load of 1.77 Nm before motion ceases. The permanent magnets generate a back electromotive force of 17.73 V/kRPM, a parameter the controller uses for voltage-mode speed estimation. Low flywheel effect is achieved with a rotor inertia of 7.1 × 10⁻⁵ kg·m², enabling rapid reversals and minimizing settling time in precision positioning tasks.