Cause: Safety Function Error comes when a problem with the drive's safety functions, which are critical for ensuring the safe operation of the drive and connected machinery.

"SAFF" fault in Schneider ATV950 drive indicate "Safety Function Error". This means a critical issue within a system's safety mechanisms. These functions are designed to protect personnel, equipment, and the environment from potential hazards.

Here’s a structured approach to troubleshoot and resolve this issue:

1. Initial Power Cycle:

• Restart the Drive: Completely power off the drive, wait for a few minutes, and then power it back on. This can sometimes clear transient errors.

2. Check Safety Function Configuration:

• Safety Parameters: Verify that all safety function parameters are configured correctly in the drive’s settings.
• Manual Verification: Refer to the drive’s user manual to ensure that safety functions are set up according to the manufacturer's recommendations and your application requirements.

3. Inspect Safety Wiring and Connections:

• Safety Circuit Wiring: Check the wiring of the safety circuits, including STO inputs, emergency stop circuits, and any other safety-related connections.
• Integrity of Connections: Ensure that all connections are secure and free from damage or corrosion.

4. Test Safety Inputs and Outputs:

• Safety Inputs: Verify that the safety inputs to the drive are functioning correctly. Use a multimeter or other testing device to check the signals.
• Safety Relays and Sensors: Check any safety relays, sensors, or switches connected to the drive. Ensure they are operating correctly and sending the appropriate signals to the drive.