Home > Nema 42 Closed Loop Stepper Motor
| Item | Specifications |
|---|---|
| Step Angle Accuracy | ±5% |
| Resistance Accuracy | ±10% |
| Inductance Accuracy | ±20% |
| Encoder | 1000-line incremental |
| 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) | Holding Torque (N・m) | Encoder (line) | Rotor Inertia (g・cm²) | Leads | Weight (kg) |
| 110BYG350-151-CL | 1.2 | 151 | 12.6 | 4.5 | 13 | 1000 | 3600 | 4+ENC | 4.8 |
| 110BYG350-185-CL | 1.2 | 185 | 10.7 | 5 | 16 | 1000 | 5800 | 4+ENC | 6.5 |
| 110BYG350-219-CL | 1.2 | 219 | 10 | 5 | 20 | 1000 | 9000 | 4+ENC | 9.5 |
| 110BYG350-285-CL | 1.2 | 285 | 14.5 | 5 | 25 | 1000 | 9000 | 4+ENC |
*These are representative models. We can manufacture products according to customer's requirements.
A closed loop NEMA 42 stepper motor is a 110mm hybrid stepper — the largest closed loop frame — with an encoder on the rear shaft. The encoder reports rotor position to a closed loop stepper driver, which corrects following error in real time, so this very-high-torque frame never loses steps under heavy load. It runs at a 1.8° step angle (200 steps per revolution).
An open-loop NEMA 42 follows step pulses with no feedback and can lose position under overload — costly on a large axis. A closed loop NEMA 42 adds a 1000-line encoder and a closed loop driver, so the system tracks true position and corrects it. The result is no lost steps, lower heating, and a position-error alarm — important on heavy machines that run unattended.
Our closed loop 110BYG250 range runs a 1.8° step angle with a 1000-line incremental encoder. Holding torque runs from about 12 N·m on the 115mm body up to 20 N·m on the 201mm body, with rated current 5.5–6.0 A/phase. Full specs are in the table and the downloadable datasheet.
A closed loop NEMA 42 needs a high-current closed loop stepper driver that reads the encoder and closes the position loop. Rated current is 5.5–6.0 A/phase, and a high bus voltage (60–110VDC) is required on this large frame to hold torque at speed. We supply a matched closed loop driver set up for the motor.
A closed loop NEMA 42 gives very high holding torque with no-lost-step reliability at lower cost than a servo, ideal for heavy axes running at low to moderate speed. An AC servo is the better choice when the axis must move fast with high dynamic response and continuous duty. See our servo-motors range for that option.
Yes. Shaft diameter and length, keyway, dual-shaft, lead length and connector, encoder line count, and winding voltage/current are all made to your drawing. A mounting bracket and a planetary or worm gearbox are also available.
The closed loop NEMA 42 stepper motor is a 110mm hybrid stepper — the largest closed loop frame — with an encoder on the rear shaft. The encoder feeds rotor position back to a closed loop stepper driver, which corrects following error in real time, so this very-high-torque frame never loses a step under heavy load. It keeps the 1.8° step angle and the high holding torque of the open-loop NEMA 42, but adds feedback reliability at a fraction of a servo's cost. A NEMA 42 closed loop stepper motor delivers holding torque from about 12 N·m to 20 N·m depending on body length.
| Parameter | Specification |
|---|---|
| Frame Size | 110 × 110 mm |
| Step Angle | 1.8° (200 steps/rev) |
| Type | Closed loop (encoder feedback) |
| Encoder | 1000-line incremental |
| Holding Torque | 12–20 N·m |
| Rated Current | 5.5–6.0 A/phase |
| Body Length | 115–201 mm (varies by model) |
| Shaft | 19mm with keyway |
This is the largest stepper frame, used on the heaviest axes — exactly where a lost step is most expensive. Closed loop removes that risk while keeping the very high torque:
The trade-off versus a servo is top speed and dynamic response; for fast heavy axes, a servo is the better fit.
The closed loop NEMA 42 is for the heaviest stepper-driven axes that can't tolerate a missed step:
With a gearbox the same frame drives an extreme-torque, low-speed axis with feedback intact.
Both are 110mm frames with the same base motor. The difference is feedback:
| Closed Loop NEMA 42 | Open Loop NEMA 42 | |
|---|---|---|
| Feedback | 1000-line encoder | None |
| Lost steps | Corrected | Possible under overload |
| Heating | Lower (regulated current) | Higher (full current) |
| Cost | Higher | Lower |
Pick closed loop when a missed step on a heavy axis is unacceptable or the machine runs unattended. Pick the open-loop NEMA 42 stepper motor when cost leads and the load is steady. Both are 110mm, so they share mounting. For fast heavy axes that need high speed, an AC servo motor is the better answer.
Cymotorix closed loop NEMA 42 stepper motors can be customized for OEM integration. As a closed loop NEMA 42 stepper motor manufacturer and supplier, we produce them to your specification. Common modifications include:
A closed loop NEMA 42 runs on a high-current closed loop stepper driver, which reads the 1000-line encoder and closes the position loop, correcting following error and raising an alarm if error exceeds a set limit. It accepts step/direction pulses like an open-loop system, so it drops into existing controls. Rated current is around 5.5 to 6.0 A/phase, so a heavy-duty driver is needed. We supply a matched closed loop driver set up for the motor if you want the pair tested together.
Recommended supply voltage is 60–110VDC. This is the largest closed loop frame, with high winding inductance, so a high bus voltage is essential to hold torque at speed. Because the driver regulates current to the load, a closed loop motor runs cooler than the same motor driven open-loop at full current.
