Posted to News on 21st Sep 2026, 11:00
Functional safety built into FIO Drive Control
Kendrion introduces the FIO Drive Control STO, marking its first integration of a SIL 3/PL e-certified Safe Torque Off (STO) function into the modular FIO drive solution.
This compact 4-quadrant servo drive for stepper and BLDC motors incorporates the dual-channel STO directly into the module, allowing safe torque shutdown without needing an extra STO module, all within a mere 25 mm of width.
Functional safety can quickly hinge on available installation space, especially in compact, decentralised machine architectures. At the same time, drives used in applications such as small-scale robotics, handling systems, automated guided vehicles and medical and laboratory equipment must stop reliably in hazardous situations without additional safety modules and without causing lengthy restart times. This is precisely where Kendrion's FIO Drive Control STO comes in.
The module, measuring only 25 120 90 mm, can be compactly mounted on a DIN rail. In the event of a safety trigger, the output power is safely cut off within a few milliseconds through two independent channels. EtherCAT communication and logic power remain operational, maintaining position and communication status. After the safety circuit is released, the drive can restart immediately without rebooting or rehoming, reducing restart times after a safety stop and minimizing machine downtime.
Safety and drive control in a single module
Besides the certified STO function, the FIO Drive Control STO offers extra features for compact drive systems. It includes an integrated power output that allows direct control of holding magnets, locking mechanisms, or parking brakes, minimising the need for additional electronics. Depending on the application, the drive can function sensorlessly or employ standard encoder interfaces for applications requiring higher positioning accuracy.
"Our goal was not to treat functional safety as an add-on module alongside the drive, but to integrate it directly into the drive solution. This makes it easier to implement compact machine concepts with less additional hardware," says Mirko Lepeschka, Application Engineer for Industrial Control Systems at Kendrion.
