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 |
Discover the Advantage of Coreless DC Motors Today
In the dynamic landscape of power solutions, our focus on coreless dc motors sets us apart as a premier provider in Pennsylvania. At MJK Inc., we are dedicated to supplying cutting-edge motion technology tailored to various industrial applications. As experts in motor control systems and gear motor manufacturing, we excel in creating robust and efficient solutions that enhance operational efficiency. By understanding the unique needs of our clients, we develop custom motor components and high-quality assemblies designed to maximize performance. Join us in powering your innovations and experience the reliability our coreless dc motors can bring to your operations.
Where Can I Find Coreless DC Motors in Pennsylvania?
In the dynamic world of motion technology, our focus on delivering exceptional coreless dc motors
sets us apart. Serving Pennsylvania, we pride ourselves on being a leader in the electric motor industry. Our dedication to quality ensures that our coreless dc motors
provide optimal performance for various applications. Understanding that precision matters, we design coreless dc motors
that are finely engineered to meet your specifications. From advanced servo systems to precision gear motors, our coreless dc motors
are crafted to enhance efficiency and reliability. Your success is our priority, and with our innovative solutions, your projects will benefit from our commitment to excellence. Partner with us to explore how our coreless dc motors
can help your business achieve its goals while fostering innovation and productivity.
contact the mjk inc. team today
Our strengths are exemplified through unparalleled quality, innovative design, and dedicated customer support. Contact our team today to learn more.
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