ETEL TMA0140‑070‑3RB‑S62B Torque Motor

The ETEL TMA0140‑070‑3RB‑S62B is a direct‑drive torque motor designed for precision rotary motion applications requiring high torque density, smooth operation, and minimal maintenance. As part of ETEL’s TMA series, this motor eliminates the need for mechanical transmissions such as belts, gears, or reducers, resulting in higher stiffness, zero backlash, and improved dynamic performance. It is ideal for applications like direct‑drive rotary tables, indexing units, and robotics.

This model features a maximum continuous torque of approximately 7 Nm and a peak torque capability of up to 18 Nm, depending on thermal and electrical conditions. It incorporates a three‑phase, brushless design with high‑grade neodymium magnets for optimal flux density. The motor is equipped with an integrated resolver for precise position feedback, ensuring accurate positioning and velocity control. A built‑in temperature sensor protects against overheating.

The TMA0140‑070‑3RB‑S62B uses air cooling (or optional water cooling) to dissipate heat, enabling continuous high‑torque operation. Its robust housing is sealed to protect against dust and moisture, making it suitable for harsh industrial environments. The motor’s low cogging torque and sinusoidal back‑EMF ensure smooth rotation at low speeds, essential for high‑precision tasks.

Technical Specifications

Frame size: 140 mm diameter. Rated torque (continuous): 7 Nm. Peak torque: 18 Nm. Rated speed: 300 rpm (depending on drive). Voltage: 300 VDC (motor). Winding configuration: Y (star). Inductance: 1.5 mH. Resistance: 0.15 Ω. Feedback: resolver (2‑pole). Cooling: air cooling (or water optional). Protection class: IP54 (standard). Weight: 4.5 kg.

The motor’s outer diameter is 140 mm, with a shaft diameter of 25 mm (hollow or solid options). It is compatible with standard ETEL servo drives (DSB series) and can be operated with other third‑party drives using appropriate setup parameters. The motor includes a thermal switch (PTC) for overtemperature protection.

Applications and Benefits

This torque motor is commonly used in semiconductor manufacturing equipment, precision rotary tables for machining centers, laser cutting machines, and medical devices. Its direct‑drive nature eliminates wear from gears and belts, resulting in lower maintenance costs and higher reliability. The high torque‑to‑inertia ratio allows fast acceleration and deceleration cycles, improving productivity. The motor’s smooth operation at low speeds is critical for precision applications such as wafer inspection or alignment.

Installation and Commissioning

Install the motor on a rigid mounting surface with proper alignment to ensure concentricity and runout within specified limits. Connect the power, feedback, and cooling lines according to the wiring diagram. Commissioning requires configuring the drive parameters (motor constants, commutation offset, current limits) using ETEL’s MotionWizard or equivalent software. Perform autotuning to optimize the control loops and verify motion performance.

Reliability and Support

ETEL torque motors are known for their durability and precision. Each unit is tested for electrical and mechanical performance, insulation resistance, and temperature rise. The motors are backed by ETEL’s global service network and comprehensive warranty.

Conclusion

The ETEL TMA0140‑070‑3RB‑S62B torque motor offers outstanding performance for direct‑drive rotary applications. Its high torque density, precise motion, and robust construction make it a preferred choice for demanding industrial automation and precision engineering.