All-new technology for rotary heat exchangers

The next generation drive for rotary heat exchangers is here. It is based on all-new, patented technology including a field oriented sensorless motor control combined with a stepper motor.

Combining a high-torque stepper motor with field oriented sensorless control brings you a unique new solution – and great efficiency. The drive uses the feedback signal from the motor to ensure that the motor gets exactly the level of current required to achieve the desired speed and torque.

The closed-loop control makes it possible to detect the motor load, and a sophisticated software algorithm allows the drive to detect rotor rotation, eliminating the need for a physical rotation monitor. In brief, field oriented sensorless motor control makes operation more silent, more accurate and more energy-efficient.

The OJ DRHX product range covers the full range from 1Nm to 14Nm in three drive power sizes (55W, 220W and 690W). Four different MRHX steppers motor sizes are available to ensure optimum use of application workspace.

DRHX drives 
an excellent new alternative to geared motors

DRHX is an advantageous new alternative to traditional geared motor solutions. In contrast to geared motors, which lose torque at low and high speed, the stepper motor provides even torque throughout the entire speed range. The linear stepper motor torque curve means that rotor speed can be accurately controlled throughout a much wider range. This enables energy-efficient heat recovery and more precise temperature control.

Sensorless rotation monitor

The DRHX is equipped with a patented solution: sophisticated software monitors the rotation of the rotor, which means that no physical/optical rotor monitor is required. Naturally, fewer components also means that you get easier installation.

Sensorless closed-loop control 

Combining a high-torque stepper motor with closed-loop sensorless control brings you a unique, patented solution – and great efficiency: The drive uses the feedback signal from the motor to ensure that the motor gets exactly the level of current required to achieve the desired speed and torque.

MRHX stepper motors 

ideal for use with the DRHX drive

The MRHX stepper motor provides an even torque curve throughout the entire speed range from 1 to 250 rpm. The rotor can be accurately controlled over a wide operating range, resulting in energy-optimised heat recovery and precise temperature control.

Direct drive 

To achieve correct rotor speed, simply mount a suitable pulley on the shaft of the MRHX stepper motor. Energy loss is reduced due to the non-gear solution, which means that motor power is utilized to its maximum. This also helps prolong the lifespan of the equipment and minimize service costs.

Hygroscopic applications 

The OJ solution supports hygroscopic rotors that typically require a higher speed than traditional rotors. The required speed of a hygroscopic rotor is between 25 and 40 rpm. Depending on application and torque requirement, you can either upgrade in motor size or select a larger pulley.

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