Safe torque off active

What does F30620 mean?

The Safe Torque Off (STO) function is active, meaning the motor's torque-generating energy is prevented, and the motor is freely rotating or at a standstill. This is a safety state initiated to prevent unintended startup, not necessarily a fault.

• STO safety input (e.g., terminals DI0, DI1, or Profisafe telegram bit) has been de-energized or set to the safe state.
• External emergency stop circuit activated, triggering STO via a safety relay (e.g., K1).
• Internal safety function (e.g., SS1, SSP) transitioned to STO after bringing the motor to a stop.
• Short circuit or wire break in the STO safety input circuit, causing loss of enabling signal.
• Incorrect parameterization of STO response (e.g., P30600, P30601) leading to unexpected activation.

Click steps to track your progress.

1. 1

   Verify the status of the STO safety input signals by measuring voltage at the dedicated terminals (e.g., X1:DI0, X1:DI1) or checking Profisafe status word (r0945.x).

2. 2

   Examine the external safety chain (e.g., E-stop buttons, safety gate switches, safety relays) to ensure all contacts are closed (e.g., continuity test across relay contacts).

3. 3

   Confirm that no upstream safety function (e.g., SS1) is intentionally activating STO by monitoring diagnostic bits r0947.x.

4. 4

   Measure voltage across the STO terminals to ensure the required 24VDC is present for deactivation (e.g., 24VDC between X1:DI0 and X1:DI_RET).

5. 5

   Reset the safety input or the upstream safety controller (e.g., F-PLC) to remove the STO activation command.