NEMA 17 Closed-Loop Stepper Motor with Planetary Speed Reducer Gearbox

This advanced NEMA 17 gear motor combines a closed-loop hybrid stepper, a
high-precision planetary gear reducer gearbox, and a 1000-line optical encoder.
It provides extremely stable torque, excellent repeatability, and precise position feedback for
industrial applications requiring high reliability.
The integrated speed reducer gearbox offers multiple planetary gear ratios to maximize torque while maintaining superior transmission efficiency.

Key Features

• 0.9° high-accuracy step angle for precise motion
• Closed-loop control with optical encoder feedback
• High-precision planetary gear reducer gearbox
• Multiple gear ratios available (1–70)
• High torque and low backlash design
• Low noise & long service life

1. Motor Dimension

Motor Size	42 × 42 mm (NEMA 17)
Total Length	Varies with gearbox level (see Gearbox Table)
Shaft Diameter	Φ 8 mm
Mounting Hole	M3 × 10

2. Motor Electrical Parameters

Item	Value
Step Angle	0.9° ±5%
Number of Phase	2
Rated Voltage	2.8 VDC
Phase Current	2.0 A
Phase Resistance	1.4 Ω ±10%
Phase Inductance	3.0 mH ±20%
Static Torque	0.44 N·m
Insulation Class	Class B
Ambient Temperature	-20°C ~ +50°C
Motor Weight	Approx. 0.5 kg
Use Voltage	DC 24–36V

3. Speed Reducer Gearbox Specification

Level	Exact Gear Ratio	Rated Load (N·m)	Gearbox Length (mm)
Level 1	3 / 4 / 5/10	8 / 9 / 9/5	40
Level 2	12/16 / 20 / 25 / 35 / 40 / 50 / 70	10/10 / 10 / 10 / 10 / 10 / 10 / 10	51

4. Encoder Specification

Item	Value
Pulse per Revolution	1000 Lines
Power Supply	+5V (Red)
Ground	GND (White)
Encoder A+	Black
Encoder A-	Blue
Encoder B+	Yellow
Encoder B-	Green

5. Wiring Diagram

Color	Description
Black	A+
Blue	A-
Yellow	B+
Green	B-

6. Excitation Sequence & Rotation Direction

Step	A+	B+	A-	B-
1	+	+	–	–
2	+	–	–	+
3	–	–	+	+
4	–	+	+	–

FAQ

What is a planetary speed reducer gearbox?

A planetary speed reducer gearbox uses multiple planetary gears revolving around a central sun gear,
providing high torque density, low backlash, and excellent transmission efficiency.

Why combine a closed-loop stepper motor with a gearbox?

The gearbox increases torque while the closed-loop encoder ensures precision positioning and eliminates missed steps,
making it ideal for demanding automation tasks.

Where is a NEMA 17 planetary gear motor typically used?

It is widely used in CNC machines, robotics, 3D printers, semiconductor equipment, medical devices, and industrial automation systems.

Download Datasheet

Download the full specification sheet for detailed parameters, wiring guide, and performance curves.

📄 Download PDF Datasheet