ADVANCED Motion Controls has announced its FlexPro series of servo drives has achieved TUV Rheinland certification for Safe Torque Off (STO).
This latest certification broadens the company's catalog of STO-approved products, including the long-standing DigiFlex Performance series, offering customers more options for safety-critical applications. The certification is effective as of Aug. 11, 2025, and applies to all FlexPro FE, FM, FD, FMP, FXE, and FXM models.
Safe Torque Off is a reliable stop function that can act upon a motor without corrupting data or leaving the system liable to mechanical errors. It allows power to be cut from servo and stepper motors without causing damage to the drive or surrounding parts of the motor. That’s why STO can be found in industry applications ranging from conveyor systems to robotics.
The STO function ensures that no torque can act upon the motor by blocking electrical signals from the power devices to the motor. This is much more robust than a simple software disable.
STO remains the trusted safety function of most servo manufacturers because it can prevent motor shaft rotation from restarting unexpectedly during emergency procedures. The only way to reactivate a servo motor after the use of the STO function would be to manually reactivate it from the controller after STO is disabled.
The FlexPro servo drive series is ADVANCED Motion Controls’ answer to the growing industry demand for compact motion control solutions that don’t compromise on power or performance. Achieving such high power-density is only possible through meticulous selection of the materials and layouts for the baseplate, boards, pins, connectors and the electronic components themselves. The power devices and switching technology are carefully designed to optimize power, efficiency and reliability with minimal thermal losses.
FlexPro servo drives are ideal for mobile robots, fixed robots, cobots, aerospace, and portable devices where space and weight are critical.
Their compact size allows for distributed installation near motors or even within motor housings, reducing the noise and cost associated with long cable runs.
In battery-powered applications, such as mobile robots, lighter components translate to better efficiency, meaning more time in operation and less time on the charger. The high current ratings enable handling intense torques and moving heavy loads that would previously have required bigger and heavier servo drives.
