Pacific Scientific Sigmax II M21NRXC-LDN Stepping Motor 1/4x3/4 Double Shaft

Pacific Scientific Sigmax II M21NRXC-LDN Stepping Motor 1/4x3/4 Double Shaft

The Pacific Scientific Sigmax II M21NRXC-LDN is a two-phase hybrid stepping motor from Pacific Scientific's Motor & Control Division. It features a double-ended output shaft — a practical configuration for applications requiring encoder feedback or dual-axis mechanical coupling — and connects via an 8-pin inline connector. The Sigmax II series was Pacific Scientific's precision stepping motor line, designed for high-torque-per-frame-size performance in demanding motion control applications.

Specifications & What's Included

• Make: Pacific Scientific Motor & Control Division
• Series: Sigmax II Stepping Motor
• Model: M21NRXC-LDN
• Shaft Configuration: Double shaft
• Shaft Diameter: 1/4 in (approx. 6.35 mm)
• Shaft Length: 3/4 in (approx. 19.05 mm)
• Connector: 8-pin inline connector (pins numbered 2–8 visible on connector body)
• Frame: Square-flange body with four mounting holes, NEMA 23-compatible form factor
• Motor only — no driver, cable, or accessories included

Applications

Stepping motors like the Pacific Scientific Sigmax II are used in precision motion control systems where exact positional control is needed without a closed-loop encoder (or with an encoder mounted to the second shaft). Common applications include CNC machinery, automated assembly equipment, semiconductor handling, laboratory instrumentation, robotics, and multi-axis positioning stages. The double-shaft design is particularly useful in setups where an encoder or tachometer is mounted to the rear shaft for position feedback, while the front shaft drives the mechanical load. Pacific Scientific's Sigmax II series was a well-regarded product line from the 1980s and 1990s, widely deployed in industrial automation and precision equipment of that era. Replacement units and spares remain in demand for maintaining legacy systems built around Pacific Scientific motion control platforms.