The HVAC unit’s test system for temperature and recirculation control lifetime uses three control heads. Two control rotary temperature and exhaust regulators; the third head is designed to control the recirculation rod and generate a linear movement.

DC motors with planetary gearbox are used for control. The control torque is transmitted via a mechanical clutch with adjustable torque. A multi-turn potentiometric angular position sensor senses the position.

This measuring system supports the adjustment of the positions of the controls, which are then repeated in a large number of cycles. It is possible to repeat each movement many times according to the defined scenario. The program monitors the movement of the controls during the measurement. If the control stops moving (usually because the control grids in and mechanical clutch start slipping), it records the time the failure occurred (including other data, such as how many cycles the failure occurred), and the motor stops movement. At the end of the measurement, the system generates a report.

The LabJack module is used for measurement. The module is connected by a USB bus to the measuring computer, providing program control of the system.

More information request here.