ETEL TMB0291‑050‑3TDS‑E82 Torque Motor

The ETEL TMB0291‑050‑3TDS‑E82 is a direct‑drive torque motor designed for high‑precision rotary motion applications requiring exceptional torque density, smooth operation, and minimal maintenance. As part of ETEL’s TMB 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, robotics, and machine tool spindles.

This model features a maximum continuous torque of 50 Nm and a peak torque capability of approximately 150 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 or encoder for precise position feedback, ensuring accurate positioning and velocity control. The built‑in temperature sensor allows protection against overheating, enhancing reliability.

The TMB0291‑050‑3TDS‑E82 uses water cooling (or air 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: 291 mm diameter. Rated torque (continuous): 50 Nm. Peak torque: 150 Nm. Rated speed: 300 rpm (depending on drive). Rated power: approximately 1.5 kW. Voltage: 300 VDC (motor). Winding configuration: Y (star). Inductance: 2.5 mH. Resistance: 0.2 Ω. Feedback: resolver (2‑pole) or EnDat absolute encoder (optional). Cooling: water cooling (flow rate 4 L/min) or forced air. Protection class: IP54 (standard). Weight: 28 kg.

The motor’s outer diameter is 291 mm, with a shaft diameter of 60 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.

The water‑cooled design enables continuous duty operation at high torque, suitable for heavy‑duty applications. Its compact size relative to torque output allows space‑saving machine designs. The integrated feedback options simplify system integration and enhance control accuracy.

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. The motor includes grounding terminals and shielding provisions for electromagnetic compatibility.

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. Spare parts and repair services are available.

Conclusion

The ETEL TMB0291‑050‑3TDS‑E82 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.