Product Description:

The M21NRXC-LNN-NS-02 is a two-phase, open-loop stepper motor built by Pacific Scientific and supplied within the POWERMAX II M Motors series. It is intended for incremental positioning duties in automated machinery. The unit receives sequential current pulses from a drive and converts them into fixed shaft increments so that indexers, labeling stations, or small gantries can move to repeatable angular targets under electrical control. Because it operates open loop, motion depends on commanded pulse counts rather than closed-loop correction during normal use.

Mechanically, the rotor follows a 200-step cycle with a 1.8 degrees step angle, giving 1.5% accuracy per move. The frame is the NEMA 23 size and contains one magnetic stack, a standard rotor, and enhanced construction for improved stiffness. With phase windings coded C, the motor draws 3.5 A in parallel connection, where the coil has 0.53 Ω of resistance and 2.0 mH of inductance. At that current, it produces 144 oz-in of static holding torque, while detent torque is 9.4 oz-in when de-energized. Thermal resistance from the winding to the case is 5.5 °C/W, and the insulation is Class B rated to 130 °C with 100 MΩ resistance and 340 Vdc dielectric strength. Electrical connections are provided through a regular lead-wire receptacle, and no encoder feedback is included.

The motor operates in ambient temperatures from -20 °C to +40 °C and weighs only 1.5 lb, which helps keep moving-axis mass low. A single smooth shaft accepts axial force up to 13 lb and radial force up to 20 lb without exceeding bearing life ratings. The mounting interface follows standard NEMA dimensions, and the internal insulation system helps maintain step integrity under elevated humidity. Rotor inertia is 0.0017 oz-in-s², and the sealed windings help resist moisture ingress during continuous duty.