High Precision NEMA 17 Permanent Magnet Stepper Motor – 7.5° Step Angle, 12V, 0.5kg.cm Holding Torque

NEMA 17 Permanent Magnet Stepper Motor Overview

This 3-phase NEMA 17 permanent magnet stepper motor is designed for compact motion control with clear wiring and excitation sequence. The drawing shows the six-wire outputs and mounting dimensions for accurate integration.

Key Features

• • 3-phase permanent magnet rotor — stable low-speed torque
  • 7.5° step angle
  • 12 VDC phase voltage, 171 mA phase current
  • Holding torque: 500 g·cm (min)
  • Compact NEMA 17 (42 mm) frame

Dimensional Drawing

Dimension	Value
Frame Size	42 mm (NEMA 17)
Shaft Diameter	Φ3 mm
Shaft Length	12 ± 0.5 mm
Motor Length	22.1 mm
Mounting Hole Spacing	49.5 ± 0.2 mm
Approx. Weight	≈ 0.1 kg

Electrical & Performance Specifications

Item	Specification
Step Angle	7.5°
Number of Phases	3
Phase Voltage	12 VDC
Phase Current	171 mA
Phase Resistance	70 Ω ±7% (@20°C)
Holding Torque	500 g·cm Min
Pull-in Torque	110 g·cm Min @ 200 pps
Detent Torque	100 g·cm Max
Start Rate	300 pps Min
Phase Inductance	50.93 mH ±20%

Wiring Diagram (as shown in drawing)

Exactly as on the supplied drawing — six wires with labels A / B / C / D / O / M.

Wire Color (EN)	Label (drawing)	Comment
Yellow	A	Left-top coil end — labeled “YEL A” on drawing
Red	O	Left-middle coil end — labeled “RED O” on drawing
Orange	C	Left-bottom coil end — labeled “ORG C” on drawing
Black	B	Right-top coil end — labeled “BLK” under “B” on drawing
Red (second)	M	Right-middle coil end — labeled “RED” under “M” on drawing
Blue	D	Right-bottom coil end — labeled “BLU” under “D” on drawing

Notes: The drawing lists six separate wires in two vertical groups — A / O / C on the left (YEL / RED / ORG) and B / M / D on the right (BLK / RED / BLU). The two red wires are distinct (one is labelled O, the other M).

Excitation Sequence and Direction (exact table from drawing)

Seen from the mounting surface (viewed from shaft side) — sequence and polarity reproduced exactly as in the drawing.

STEP	A	B	C	D	O	M
1	–	–			+	+
2		–	–		+	+
3			–	–	+	+
4	–			–	+	+

Direction: the drawing shows clockwise (CW) as top→bottom in the table and counterclockwise (CCW) reversed. Follow the sequence accordingly when driving the phases.

Applications

• Compact automation and positioning systems
• 3D printers and lab equipment
• Small robotics and security devices

FAQ (Concise, technical)

What is a permanent magnet stepper motor?
A motor whose rotor contains permanent magnets; stator windings are sequentially energized to step the rotor to discrete positions.

Difference between permanent magnet and variable reluctance stepper motor?
PM steppers use rotor magnets and provide higher torque and holding force; VR steppers use a soft-iron toothed rotor with no magnets and rely on reluctance, usually giving lower torque and coarser detent behavior.

Permanent magnet stepper motor advantages and disadvantages?
Advantages: good low-speed torque, distinct detent/holding, simple control. Disadvantages: limited microstep resolution and lower high-speed torque compared with hybrid steppers.

What is the Permanent Magnet Stepper Motor Working principle?
Sequential excitation of stator windings creates rotating magnetic fields which align the permanent-magnet rotor step-by-step.

Permanent magnet vs hybrid stepper motor?
Hybrid combines PM and VR features to achieve higher torque density and resolution; PM-only units are simpler and cost-effective for small, lower-resolution applications.

We are capable of wiring customization and can provide a labeled cable with colors exactly as shown (YEL / RED / ORG / BLK / RED / BLU).

Download Datasheet

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

📄 Download PDF Datasheet