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 |
Experience Precision Engineering with Coreless DC Motors Today
Driving innovation in motion technology is our mission at MJK Inc. We are proud to offer exceptional solutions specializing in coreless dc motors that cater to diverse application needs. Our expertise in developing precision-engineered gear motors and servo systems ensures that we meet your unique requirements with efficiency and reliability. As a trusted partner for businesses in the area, we are dedicated to delivering high-performance products that enhance productivity. Explore how our coreless dc motors can elevate your projects to new heights. Contact us today to discuss your needs.
Where Can I Find Coreless DC Motors in North Carolina?
In the realm of advanced motion technology, finding the perfect solution can be a game changer for your operations. We are proud to serve North Carolina with our unmatched offerings, including our state-of-the-art coreless dc motors. With extensive experience in manufacturing bespoke motor control systems, we specialize in creating efficient coreless dc motors
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