Home > Nema 17 Stepper Motor
| Item | Specifications |
|---|---|
| Step Angle Accuracy | ±5% |
| Resistance Accuracy | ±10% |
| Inductance Accuracy | ±20% |
| Temperature Rise | 80°C Max. |
| Ambient Temperature | -20°C ~ +50°C |
| Insulation Resistance | 100MΩ Min. 500VDC |
| Dielectric Strength | 500V AC 1 minute |
| Allowable Radial Load | 0.02mm Max. (450g load) |
| Allowable Thrust Load | 0.08mm Max. (450g load) |
| Model | Step Angle (°) | Length (mm) | Voltage (V) | Current (A/phase) | Resistance (Ω/phase) | Inductance (mH/phase) | Holding Torque (N·m) | Rotor Inertia (g·cm²) | Leads | Weight (kg) |
| 42BYG250-34 | 1.8 | 33 | 2.76 | 1.2 | 2.3 | 2.5 | 0.22 | 35 | 4 | 0.22 |
| 42BYG250-40 | 1.8 | 39 | 2.55 | 1.5 | 1.7 | 3.4 | 0.3 | 54 | 4 | 0.28 |
| 42BYG250-48 | 1.8 | 47 | 2.7 | 1.5 | 1.8 | 3.2 | 0.4 | 68 | 4 | 0.35 |
| 42BYG250-60 | 1.8 | 59 | 3.3 | 1.2 | 2.75 | 6.4 | 0.6 | 102 | 4 | 0.46 |
*These are representative models. We can manufacture products according to customer's requirements.
NEMA 17 torque depends on body length. Our 42BYG250 range runs from about 0.22 N·m on the 34mm body up to 0.65 N·m on the 60mm body, all at a 1.8° step angle. Pick the longer body when you need more torque in the same 42mm footprint.
A NEMA 17 stepper motor has a 42mm × 42mm faceplate — the NEMA 17 size that's become the default for 3D printers and small CNC. Body length runs 34mm to 60mm across our models, standard shaft is 5mm, and full specs are in the table and the downloadable datasheet.
At a 1.8° step angle, a NEMA 17 takes 200 steps per revolution. A 0.9° version doubles that to 400 steps for finer resolution. With microstepping, the driver can subdivide each step much further for smoother motion.
Max RPM depends on the driver, supply voltage, and load, not just the motor. With a higher bus voltage (24–48V) and a good microstepping driver, a NEMA 17 commonly runs up to around 1000–1500 RPM, though usable torque drops as speed rises. For steady high-speed work, size for torque at running speed, not holding torque.
A NEMA 17 runs on any standard 2-phase stepper driver. Rated current is around 1.5–2.0 A/phase, so a mid-range microstepping driver suits it. Recommended supply is 12–48VDC — higher voltage improves high-speed torque. We can supply a matched driver sized and set for the motor.
Yes. Shaft diameter and length, D-cut or flat shaft, pinion or gear shaft, lead length and connector (JST, Molex, bare leads), and winding voltage/current are all made to your drawing. A 0.9° version, rear-shaft encoder, pancake short body, and planetary gearbox are also available.
If your load fits within about 0.65 N·m and the 42mm footprint works, NEMA 17 is the right call — it's the most widely supported frame. If you need substantially more torque, step up to NEMA 23 (57mm). The comparison table below lays out the difference.
The NEMA 17 stepper motor is the most widely used stepper frame in the world. With a 42mm × 42mm faceplate, it hits the sweet spot between size and torque, which is why it drives most 3D printers, desktop CNC machines, laser engravers, and small automation. A 2-phase NEMA 17 hybrid stepper motor delivers holding torque from about 0.22 N·m to 0.65 N·m depending on body length, at a 1.8° step angle. NEMA 17 dimensions are fixed at a 42mm faceplate, with body length the main variable.
| Parameter | Specification |
|---|---|
| Frame Size | 42 × 42 mm |
| Step Angle | 1.8° (200 steps/rev), 0.9° optional |
| Phase | 2-phase (bipolar) |
| Holding Torque | 0.22–0.65 N·m |
| Rated Current | 1.5–2.0 A/phase |
| Body Length | 34–60 mm (varies by model) |
| Steps per Revolution | 200 (1.8°) / 400 (0.9°) |
| Weight | 220–460 g |
| Lead Wires | 4-wire or 6-wire |
The NEMA 17 is the default choice across small to mid-size motion. Common applications include:
With a NEMA 17 gearbox the same frame drives a linear actuator or a low-speed, high-torque axis; or add a rear-shaft encoder for feedback.
The next size up from NEMA 17 is NEMA 23 (57mm × 57mm). Here is a quick comparison:
| NEMA 17 (42mm) | NEMA 23 (57mm) | |
|---|---|---|
| Faceplate | 42 × 42 mm | 57 × 57 mm |
| Max Holding Torque | ~0.65 N·m | ~3 N·m |
| Weight | 220–460 g | 0.5–1.5 kg |
| Best For | 3D printers, desktop machines | CNC, heavier automation |
If your load needs more than about 0.65 N·m, move up to NEMA 23. If the 42mm footprint works and the load is light to moderate, NEMA 17 is the right fit — and the easiest to source drivers and parts for.
Cymotorix NEMA 17 stepper motors can be customized for OEM integration. As a NEMA 17 stepper motor manufacturer and supplier, we produce them to your specification. Common modifications include:
NEMA 17 motors are 2-phase bipolar steppers, so they run on any standard 2-phase stepper driver. A NEMA 17 stepper driver only needs to handle the rated current with some headroom. Rated current is around 1.5 to 2.0 A per phase, so a mid-range microstepping driver with current regulation gives the smoothest motion. We can supply a driver matched and set to the motor if you want the pair tested together.
Recommended supply voltage is 12–48VDC. A higher bus voltage noticeably improves high-speed torque on a NEMA 17, which is why CNC and fast-printing builds often run 36–48V. Set the driver's current limit to the motor's rated current so the windings don't overheat.
