cl series coreless dc motors
The Premotec Coreless DC motors have a maximized performance due to the use of precious metal commutation in combination with high performance magnets. As these motors are coreless there are no iron losses, no preferred rotor position and due to the use of many phases, the torque ripple is reduced to a minimum.
The CL series motor performance is summarized below.

Specifications Overview
| Frame Size (mm) | 29, 40, 66 |
| Bus Voltage (VDC) | 6 - 36 |
| Rated Speed (RPM) | 2,560 - 5,280 |
| Rated Power (W) | 3 - 25 |
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documents & resources
CL 29 Series
| Part Numbers | Voltage | Direction | Speed | Watt |
|---|---|---|---|---|
| 9904 120 18601 | 6 | REV | 4010 | 3 |
| 9904 120 18602 | 7.2 | REV | 3850 | 3 |
| 9904 120 18603 | 9 | REV | 3990 | 3 |
| 9904 120 18105 | 12 | REV | 3840 | 3 |
| 9904 120 18605 | 15 | REV | 3750 | 3 |
| 9904 120 18606 | 18 | REV | 4010 | 3 |
| 9904 120 18215 | 24 | REV | 3840 | 3 |
CL 29 Series 3 W Coreless DC Motors
SPECIFICATIONS
| Model | 9904 120 + | 18601 | 18602 | 18603 | 18105 | 18605 | 18606 | 18215 |
|---|---|---|---|---|---|---|---|---|
| Nominal Voltage | V | 6 | 7.2 | 9 | 12 | 15 | 18 | 24 |
| Nominal Torque | mNm (oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) | 10 (1.42 oz-in) |
| Nominal Speed | RPM | 2680 | 2550 | 2680 | 2440 | 2380 | 2680 | 2470 |
| Nominal Current | mA | 775 | 620 | 515 | 370 | 290 | 260 | 185 |
| No-Load Speed | RPM | 4010 | 3850 | 3990 | 3840 | 3750 | 4010 | 3840 |
| No-Load Current | mA | 67 | 52 | 45 | 31 | 24 | 22 | 16 |
| BEMF at 3000 RPM | V | 4.35 | 5.44 | 6.53 | 9.07 | 11.6 | 13.1 | 18.1 |
| Torque Constant | mNm/A (oz-in/A) | 13.9 (1.97) | 17.3 (2.45) | 20.8 (2.95) | 28.9 (4.09) | 37 (5.24) | 41.6 (5.89) | 57.7 (8.17) |
| Terminal Resistance | Ohm | 2.7 | 4.2 | 6.1 | 12.5 | 20.1 | 24.5 | 49 |
| Starting Torque at Nom. Voltage | mNm (oz-in) | 30 (4.25) | 30 (4.25) | 30 (4.25) | 27 (3.82) | 27 (3.82) | 30 (4.25) | 28 (3.97) |
| Starting Current at Nom. Voltage | A | 2.21 | 1.73 | 1.47 | 0.96 | 0.5 | 0.73 | 0.49 |
| Rotor Inductance | mH | 0.2 | 0.32 | 0.46 | 0.89 | 1.46 | 1.84 | 3.55 |
| Rotor Inertia | kgm2 (oz-in-s2) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) | 0.9E-6 (1.27E-4) |
| Mech. Time Constant | ms | 13 | 13 | 13 | 13 | 13 | 13 | 13 |
| Thermal Resistance Winding-Housing | °C/W | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 |
| Thermal Resistance Housing-Ambient | °C/W | 16.3 | 16.3 | 16.3 | 16.3 | 16.3 | 16.3 | 16.3 |
CL 40 Series
| Part Numbers | Voltage | Direction | Speed | Watt |
|---|---|---|---|---|
| 9904 120 16701 | 6 | REV | 3780 | 7 |
| 9904 120 16702 | 9 | REV | 4050 | 7 |
| 9904 120 16703 | 12 | REV | 3780 | 7 |
| 9904 120 16704 | 15 | REV | 3940 | 7 |
| 9904 120 16705 | 18 | REV | 4050 | 7 |
| 9904 120 16706 | 24 | REV | 3980 | 7 |
| 9904 120 16707 | 30 | REV | 3940 | 7 |
CL40 Series 7 W Coreless DC Motors
SPECIFICATIONS
| Model | 9904 120 + | 16701 | 16702 | 16703 | 16704 | 16705 | 16706 | 16707 |
|---|---|---|---|---|---|---|---|---|
| Nominal Voltage | V | 6 | 9 | 12 | 15 | 18 | 24 | 30 |
| Nominal Torque | mNm (oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) | 22 (3.12 oz-in) |
| Nominal Speed | RPM | 2650 | 3010 | 2700 | 2920 | 3050 | 2980 | 2930 |
| Nominal Current | mA | 1520 | 1090 | 760 | 635 | 540 | 400 | 320 |
| No-Load Speed | RPM | 3780 | 4050 | 3780 | 3940 | 4050 | 3980 | 3940 |
| No-Load Current | mA | 60 | 44 | 30 | 25 | 22 | 16 | 13 |
| BEMF at 3000 RPM | V | 4.71 | 6.59 | 9.42 | 11.3 | 13.2 | 17.9 | 22.6 |
| Torque Constant | mNm/A (oz-in/A) | 15 (2.12) | 21 (2.97) | 30 (4.25) | 36 (5.1) | 42 (5.95) | 57 (8.07) | 72 (10.2) |
| Terminal Resistance | Ohm | 1.2 | 2.2 | 4.6 | 6.3 | 8.4 | 15.6 | 25.1 |
| Starting Torque at Nom. Voltage | mNm (oz-in) | 74 (10.5) | 86 (12.2) | 77(10.9) | 85 (12) | 89 (12.6) | 87 (12.3) | 28 (3.97) |
| Starting Current at Nom. Voltage | A | 5 | 4.1 | 2.6 | 2.4 | 2.1 | 1.5 | 1.2 |
| Rotor Inductance | mH | 0.15 | 0.29 | 0.59 | 0.85 | 1.16 | 2.14 | 3.41 |
| Rotor Inertia | kgm2 (oz-in-s2) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) |
| Mech. Time Constant | ms | 20 | 20 | 20 | 19 | 19 | 19 | 19 |
| Thermal Resistance Winding-Housing | °C/W | 5.5 | 5.5 | 5.5 | 5.5 | 5.5 | 5.5 | 5.5 |
| Thermal Resistance Housing-Ambient | °C/W | 13 | 13 | 13 | 13 | 13 | 13 | 13 |
CL 40 Series
| Part Numbers | Voltage | Direction | Speed | Watt |
|---|---|---|---|---|
| 9904 120 15601 | 12 | REV | 5280 | 12 |
| 9904 120 15602 | 15 | REV | 5180 | 12 |
| 9904 120 15603 | 18 | REV | 5220 | 12 |
| 9904 120 15604 | 24 | REV | 5280 | 12 |
| 9904 120 15605 | 30 | REV | 3750 | 12 |
CL40 Series 12 W Coreless DC Motors
SPECIFICATIONS
| Model | 9904 120 + | 15601 | 15602 | 15603 | 15604 | 15605 |
|---|---|---|---|---|---|---|
| Nominal Voltage | V | 12 | 15 | 18 | 24 | 30 |
| Nominal Torque | mNm (oz-in) | 26 (3.68 oz-in) | 26 (3.68 oz-in) | 26 (3.68 oz-in) | 26 (3.68 oz-in) | 26 (3.68 oz-in) |
| Nominal Speed | RPM | 4140 | 4090 | 4150 | 4170 | 4100 |
| Nominal Current | mA | 1250 | 980 | 830 | 630 | 490 |
| No-Load Speed | RPM | 5280 | 5180 | 5220 | 5280 | 5180 |
| No-Load Current | mA | 49 | 38 | 32 | 25 | 19 |
| BEMF at 3000 RPM | V | 6.76 | 8.62 | 10.3 | 13.5 | 17.2 |
| Torque Constant | mNm/A (oz-in/A) | 21.5 (3.05) | 27.4 (3.88) | 32.6 (4.62) | 43 (6.09) | 54.9 (7.78) |
| Terminal Resistance | Ohm | 2.1 | 3.3 | 4.6 | 8.3 | 13.1 |
| Starting Torque at Nom. Voltage | mNm (oz-in) | 121 (17.1) | 123 (17.4) | 126 (17.8) | 123 (17.4) | 125 (17.7) |
| Starting Current at Nom. Voltage | A | 5.6 | 4.5 | 3.9 | 2.9 | 2.3 |
| Rotor Inductance | mH | 0.31 | 0.5 | 0.71 | 1.23 | 2.01 |
| Rotor Inertia | kgm2 (oz-in-s2) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) | 4E-6 (5.67E-4) |
| Mech. Time Constant | ms | 18 | 18 | 18 | 18 | 18 |
| Thermal Resistance Winding-Housing | °C/W | 5.5 | 5.5 | 5.5 | 5.5 | 5.5 |
| Thermal Resistance Housing-Ambient | °C/W | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
CL 66 Series
| Part Numbers | Voltage | Direction | Speed | Watt |
|---|---|---|---|---|
| 9904 120 13601 | 12 | REV | 2560 | 25 |
| 9904 120 13602 | 15 | REV | 2830 | 25 |
| 9904 120 13603 | 18 | REV | 2890 | 25 |
| 9904 120 13604 | 24 | REV | 2580 | 25 |
| 9904 120 13605 | 30 | REV | 2960 | 25 |
| 9904 120 13606 | 36 | REV | 3210 | 25 |
CL66 Series 25 W Coreless DC Motors
SPECIFICATIONS
| Model | 9904 120 + | 13601 | 13602 | 13603 | 13604 | 13605 | 13606 |
|---|---|---|---|---|---|---|---|
| Nominal Voltage | V | 12 | 15 | 18 | 24 | 30 | 36 |
| Nominal Torque | mNm (oz-in) | 100 (14.2 oz-in) | 100 (14.2 oz-in) | 100 (14.2 oz-in) | 100 (14.2 oz-in) | 100 (14.2 oz-in) | 100 (14.2 oz-in) |
| Nominal Speed | RPM | 1800 | 2090 | 2200 | 2170 | 2280 | 2540 |
| Nominal Current | mA | 2330 | 2060 | 1750 | 1300 | 1080 | 980 |
| No-Load Speed | RPM | 2560 | 2830 | 2890 | 2850 | 2960 | 3210 |
| No-Load Current | mA | 81 | 77 | 66 | 49 | 41 | 40 |
| BEMF at 3000 RPM | V | 13.9 | 15.7 | 18.5 | 25 | 30.1 | 33.3 |
| Torque Constant | mNm/A (oz-in/A) | 44.2 (6.26) | 50.1 (7.1) | 59 (8.36) | 79.6 (11.3) | 95.8 (13.6) | 106 (15) |
| Terminal Resistance | Ohm | 1.6 | 2 | 2.5 | 4.6 | 6.6 | 8 |
| Starting Torque at Nom. Voltage | mNm (oz-in) | 335 (47.5) | 384 (54.4) | 418 (59.2) | 418 (59.2) | 436 (61.8) | 477 (67.6) |
| Starting Current at Nom. Voltage | A | 7.6 | 7.7 | 7.1 | 5.3 | 4.6 | 4.5 |
| Rotor Inductance | mH | 0.59 | 0.75 | 1.04 | 1.9 | 2.75 | 3.37 |
| Rotor Inertia | kgm2 (oz-in-s2) | 21E-6 (2.97E-3) | 21E-6 (2.97E-3) | 21E-6 (2.97E-3) | 21E-6 (2.97E-3) | 21E-6 (2.97E-3) | 21E-6 (2.97E-3) |
| Mech. Time Constant | ms | 17 | 16 | 15 | 15 | 15 | 15 |
| Thermal Resistance Winding-Housing | °C/W | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 |
| Thermal Resistance Housing-Ambient | °C/W | 5 | 5 | 5 | 5 | 5 | 5 |
Power Your Innovations with Coreless DC Motors Today!
Providing tailored solutions, our commitment to quality and engineering excellence makes us a key player in delivering coreless dc motors for various applications in Michigan. We focus on innovation and reliability, and our expertise ranges from high-performance motor control systems to precision-engineered gear motors. Our custom motor solutions are designed to meet the specific needs of your project, ensuring robust performance and lasting efficiency. With MJK Inc. as your trusted partner, you can confidently elevate your operations. Contact us today to discover how our coreless dc motors can power your next endeavor.
Where Can I Find Coreless DC Motors in Michigan?
Innovative motion solutions are at our core, which is why we focus heavily on advanced technologies like coreless dc motors. Serving the Michigan area, we stand out as experts in the electric motor industry, renowned for our high-performance offerings. Our coreless dc motors
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and how they can benefit your projects.
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