NEMA 17 0.9° Stepper Motor with Planetary Gearbox

This product integrates a NEMA 17 0.9-degree stepper motor with a compact and efficient
planetary gearbox, offering higher torque output, precise speed control, and excellent durability.
The short shaft design and terminal wire connection make it ideal for space-constrained automation systems.

The stepper motor section is based on a reliable 0.9° short shaft design.
If you need the motor alone, you can refer to this model:

NEMA 17 Ultra Thin Pancake Stepper Motor

Key Features of Planetary Gearbox Stepper Motor

• High torque output with compact planetary gearbox structure
• 0.9° step angle for higher positioning resolution
• Short output shaft, suitable for limited axial space
• Terminal wire design for fast and secure electrical connection
• Multiple planetary gear ratio options available

Stepper Motor Technical Parameters

Item	Specification
Frame Size	NEMA 17 (42 × 42 mm)
Step Angle	0.9° ±5%
Number of Phases	2
Phase Voltage	3.36 VDC
Phase Current	1.4 A
Phase Resistance	2.4 Ω ±10% (20°C)
Phase Inductance	5.5 mH ±20%
Holding Torque (Motor Only)	0.18 N·m
Insulation Class	Class B
Insulation Resistance	100 MΩ min. (500V DC)
Ambient Temperature	-20°C to +50°C
Motor Weight	Approx. 0.24 kg

Planetary Gearbox Specifications

Item	Specification
Gearbox Type	Planetary Gearbox
Gear Stages	Level 1 / Level 2
Efficiency	96% (Level 1), 94% (Level 2)
Backlash	< 15 arcmin (Level 1), < 20 arcmin (Level 2)
Noise	< 55 dB
Output Shaft	Short Shaft (Customizable)

Planetary Gear Ratio Options

Reduction Ratio	Rated Load (N·m)	Gearbox Length (mm)
3 : 1	8	40
4 : 1	9	40
5 : 1	9	40
10 : 1	10	40
16 : 1	10	51
20 : 1	10	51
25 : 1	10	51
35 : 1	10	51
40 : 1	10	51
50 : 1	10	51
70 : 1	10	51

Available Planetary Gear Ratios

Gear Ratio	Application Focus	Product Page
3 : 1	High speed, low torque increase	View 3:1 planetary gearbox
10 : 1	Balanced speed and torque	View 10:1 planetary gearbox
5 : 1	Balanced speed and torque	View 5:1 planetary gearbox
20 : 1	Balanced speed and torque	View 20:1 planetary gearbox
50 : 1	Maximum torque output	View 50:1 planetary gearbox

How to Calculate Output Torque for a Planetary Gear Motor

Selecting the correct planetary gear motor requires understanding how motor torque is amplified through the gearbox.
The output torque depends on three key factors: motor torque, gear ratio, and gearbox efficiency.

Torque Calculation Formula

Output Torque (Nm) =
Motor Torque (Nm) × Gear Ratio × Gearbox Efficiency

Planetary gearboxes typically have an efficiency of 90%–95% per stage.

Example Calculation

Assume a NEMA 17 stepper motor with a holding torque of 0.45 Nm is paired with a 20:1 planetary gearbox.

Output Torque ≈ 0.45 × 20 × 0.95 = 8.55 Nm

This significant torque increase makes planetary gear motors ideal for applications such as
vertical axes, linear actuators, and precision positioning systems.

Typical Torque Gain by Gear Ratio

Gear Ratio	Torque Increase	Typical Applications
5:1	~4.3× motor torque	Light automation, fast positioning, compact mechanisms
10:1	~8.5× motor torque	Indexing tables, conveyors, small robotic joints
20:1	~17× motor torque	Linear actuators, vertical loads, precision automation
50:1	~42× motor torque	Lifting systems, heavy-duty positioning, low-speed high-load axes

Engineering Considerations

• Do not size the gearbox only based on holding torque. Always consider dynamic torque.
• Higher gear ratios reduce output speed and increase system inertia.
• For vertical loads, always include a safety factor of 1.5–2×.
• Backlash and efficiency vary by gearbox quality and number of stages.

Need Help Calculating Torque for Your Application?

If you are unsure which planetary gear ratio or motor combination fits your load and speed requirements,
our engineers can help you verify torque, speed, and service life before ordering.

✔ Load & torque calculation support
✔ Custom gear ratios and motor configurations
✔ OEM and bulk order solutions

Request Engineering Support

Wiring Diagram (Terminal Wire)

Wire Color	Function
Black (BLK)	Phase A+
Green (GRN)	Phase A−
Red (RED)	Phase B+
Blue (BLU)	Phase B−

This planetary gearbox stepper motor solution is widely used in automation equipment,robot joints, packaging machines, laboratory instruments, and positioning systems where high torque and accurate motion control are required.

Planetary Gearbox Selection Guide

Selecting the correct planetary gear ratio depends on load torque, speed requirements, and positioning accuracy.

FAQ 1: Which applications are best for a planetary gearbox stepper motor?

Planetary gear motor systems are widely used in applications that require compact size, high torque density, and precise motion control.

Typical applications include industrial automation equipment, robotic joints, linear actuators, precision conveyors, and positioning tables.

Lower ratios such as 5:1 or 10:1 are often used for speed-sensitive motion, while higher ratios like 20:1 or 50:1 are preferred for high-load or vertical axis applications.

FAQ 2: How do I choose the right planetary gear ratio for my application?

Choosing the correct planetary gear ratio depends on three key factors:

required torque, output speed, and load inertia.

5:1 – 10:1: light to medium loads, higher speed, smooth motion

20:1: balance between torque and precision positioning

50:1: heavy loads, low speed, maximum holding torque

If you are unsure, our engineers can help calculate the optimal ratio based on your motor and load parameters.

FAQ 3: Are planetary gearboxes suitable for continuous operation?

Yes. High-quality planetary gearboxes are designed for continuous industrial operation.

Thanks to multiple planet gears sharing the load, they provide excellent durability, low backlash, and stable torque transmission over long service life.

FAQ 4: Can a planetary gearbox be used with linear actuators or lead screw systems?

Absolutely. Planetary gear motors are commonly combined with lead screw actuators or linear motion systems to increase thrust force and positioning accuracy.

This configuration is widely used in automation modules, packaging machinery, and precision adjustment mechanisms.

Need Help Selecting the Right Planetary Gear Motor?

Not sure which planetary gear ratio fits your application?
Our engineering team can help you select the right gearbox, motor, and configuration based on your load, speed, and precision requirements.

✔ Custom gear ratios available
✔ OEM & bulk orders supported
✔ Fast technical response for engineers

Request a Technical Quote

Download Datasheet

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

📄 Download PDF Datasheet