stepper motors ULKollmorgen’s POWERMAX II Series stepper motors are now UL recognized. This enables OEMs who build UL-certified equipment to integrate high-performance stepper technology into existing designs without requiring re-certification. These NEMA 23 (60-mm) step motors are available in half, single and two stack configurations, and provide holding torques from 42 oz-in. to 253 oz-in. Speeds up to 3000 rpm more than satisfy the velocity demands of most high torque applications.