Product Description:

The S31GMNA-RNNM-00 is a 6-pole neodymium magnet brushless servo motor manufactured by Pacific Scientific as part of the S Brushless Motors series. It serves as a rotary actuator in industrial automation, converting commanded phase current into proportional mechanical torque for positioning and velocity control of indexing tables, gantries, and light machine tool axes. Its brushless design supports accurate motion control in systems that require repeatable response and compact motor packaging.

The motor develops a continuous stall torque of 2.2 Nm, allowing it to hold static loads without overheating. A line-to-line resistance of 16.4 Ω governs steady-state current, while the winding inductance of 41.2 mH affects current rise time and servo response. A torque constant of 1.3 Nm/ARMS links phase current to output torque, and the back EMF coefficient is 0.82 VRMS/rad/s. The motor uses metric mounting hardware, and the single-stack lamination helps keep the axial length compact. Electrical power and resolver leads exit through a motor-mounted MS connector, winding type G is used, and position feedback is handled by a size 21 frameless resolver. The unit comes without a holding brake, so position must be retained by drive torque or an external locking device when power is removed.

For short duty bursts, the rotor supplies up to 6.2 Nm of peak torque, providing margin for rapid acceleration. Dynamic response is aided by a rotor inertia of 0.18 × 10⁻³ kg·m², and the motor has a mass of 3.2 kg. The housing fits the NEMA 34 frame envelope, which supports installation in equipment designed around that mounting size. Because there is no shaft seal, fluid ingress must be prevented at the output flange. The resolver is the only feedback device, so there is no secondary feedback path on this model.