Product Description

The P-series Powermax II series by Pacific Scientific, have continually dominated the stepper motor scene, since they were first released for commercial use. The P21NRXA-LNN-NS-00 stepper motor, being a part of this series, also features the trademark high acceleration rate and good holding torque density.

According to the designated ‘P21N’ code, the motor is of standard type NEMA-23 frame and mounted with one rotor stack. It has a winding of ‘A’ category and is constructed according to the ‘regular’-construction specifications for Powermax II P-series motors. It has a receptacle for external connection. The P-series motors usually feature the same number of phases (2), along with a rotation per full step of 1.8o; this translates to a total of 200 full steps for a 360o rotation/1rev. The next ‘LNN’ designation describes the rotor type and shaft specifications: the motor has a standard rotor, and a smooth single-ended shaft. It is designed for an open-loop operation, without the option for an encoder feedback nor encoder mount. The final ‘00’ sequence number indicates that all its parts are of standard-type, with no customization. The holding torque range for this motor is between 0.57Nm and 0.81Nm, depending on the phase connection mode (with the former corresponding to unipolar connection and the latter to parallel and series connections). Its rotor has moments of inertia of 1.2 ×10-5 kgm2, even though the motor weighs a total 0.68kg. Its rated current varies from 2.8 to 5.6 Amperes (DC), phase resistance within 0.23 -0.92 ohms, and phase inductance between 0.8 and 3.2mH.

Finally, it has a detent torque of 0.028Nm, which is 3.5% of the maximum holding torque. This ensures it delivers more torque under loading, however with a slightly reduced stopping torque.