Safety concept

The device is supposed to be able to perform the safety subfunction "Safe Torque Off" in accordance with IEC 61800‑5‑2:

• The device is characterized by the optional connection of an external safety controller/safety relay. This external safety controller/safety relay disconnects the safety-related STO input via a 2-pole 24 V switching signal when a connected command device (e.g. emergency stop button with latching function) is activated. This activates the STO function of the device.
• An internal, dual-channel structure with diagnostics prevents the generation of pulse trains at the power output stage.
• Instead of a galvanic isolation of the drive from the supply system by means of contactors or switches, the disconnection of the STO input described here safely prevents the activation of the power semiconductors in the output stage. The rotary-field generation for the respective motor is deactivated even though the line voltage is still present.
• When the STO safety subfunction is activated, the generated PWM signals from the device are interrupted by the STO circuit and not transmitted to the power semiconductors.