Requirements on operation

  • Operation is only permitted within the limits specified on the data sheets. This principle applies to the external safety controller as well as to the drive unit.
  • The built-in diagnostic function is limited in the case of a permanently enabled or permanently disabled STO input. Advanced diagnostic functions are performed only upon a level change of the STO signal. This is why the safety sub-function via the STO input must be triggered with connected supply voltage at least once every 12 months for PL d according to EN ISO 13849‑1 and SIL 2 according to EN 61800‑5‑2 to achieve complete test coverage. Adhere to the following test procedure for this purpose.

[1]

Maximum 12 months for PL d/SIL 2

[2]

Internal diagnostics

[3]

High: No STO

[4]

Low: STO active

  • To achieve complete test coverage after a device reset (e.g. after connecting the supply voltage), the test transition (STO active → not active) can be started only > 700 ms later. The device signals the "ready for operation" or "STO – Safe Torque Off" state if it is not in a fault state.
  • A detected hardware fault in the internal switch-off channels for STO will lead to a locking fault state of the drive unit. If the fault is reset (e.g. by switching the supply voltage on/off or by a low level at the STO input for at least 30 ms), a complete test with internal diagnostics according to the above-mentioned test procedure must be performed. If the fault occurs again, replace the device or contact SEW‑EURODRIVE Service.