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Open-Loop Stepper Motors

Open-loop stepper motors are the industry standard for reliable, cost-effective motion control. These 2-phase hybrid stepper motors operate without feedback, making them simple to integrate and highly reliable for applications where missed steps are not critical. Adampower offers a complete range from ultra-compact NEMA8 to high-torque NEMA34, with holding torque spanning from 0.014 N·m to over 12 N·m.

Each motor in this series is built with precision-wound copper coils, high-grade magnetic steel rotors, and robust bearings to ensure long service life and consistent performance. The open-loop design eliminates the need for encoder feedback wiring, reducing system complexity and cost while maintaining excellent positional accuracy for the vast majority of positioning and speed control applications.

Available Models

ModelFrame SizeHolding Torque RangeMotor LengthTypical Application
NEMA8 (HS8)20mm × 20mm0.014 - 0.030 N·m28 - 40mmCompact instruments, micro stages
NEMA11 (HS11)28mm × 28mm0.045 - 0.120 N·m28 - 50mmSmall actuators, lab equipment
NEMA14 (HS14)35mm × 35mm0.065 - 0.220 N·m20 - 33mm3D printers, small robotics
NEMA16 (HS16)39mm × 39mm0.065 - 0.800 N·m20 - 44mmMedical devices, office automation
NEMA17 (HS17)42mm × 42mm0.160 - 0.500 N·m33 - 48mm3D printers, CNC, robotics
NEMA23 (HS23)57mm × 57mm0.400 - 3.000 N·m41 - 112mmCNC routers, industrial automation
NEMA24 (HS24)60mm × 60mm0.500 - 2.600 N·m45 - 90mmPackaging machinery, textile equipment
NEMA34 (HS34)86mm × 86mm1.200 - 12.000 N·m66 - 150mmHeavy machinery, large CNC

Common Specifications

ParameterValue
Motor Type2-Phase Hybrid Stepper
Step Angle1.8° ±5% (200 steps/rev)
Step Accuracy±5%
Insulation ClassB (130°C)
Temperature Rise80°C Max
Ambient Temperature-20°C to +50°C
Insulation Resistance100MΩ Min. (500V DC)
Dielectric Strength500V AC for 1 minute
Radial Play0.02mm Max (450g load)
End Play0.08mm Max (450g load)
Shaft OptionsSingle, Double (custom available)

Why Choose Open-Loop?

  • Cost-Effective: No encoder, fewer components, lower price
  • Simple Integration: Standard 4-lead or 6-lead wiring, compatible with all major drivers
  • Reliable: Proven technology with decades of industrial use
  • Wide Range: 8 frame sizes, dozens of torque/length combinations
  • Customizable: Shaft configurations, lead wire options, and special windings available

Last updated: 2026-05-28