Cause : Supply mains overvoltage comes when the input power supply voltage to the drive is excessively high. This can be caused by fluctuations in the power supply, incorrect settings, or issues with the electrical infrastructure.

"OSF" Supply mains overvoltage fault in Schneider ATV950 drive indicates "mains supply overvoltage" condition due to the voltage supplied to the drive has exceeded the acceptable range. This means the input power supply voltage to the drive is exceeding the permissible limits.

Follow These Steps to Correct an "OSF Supply Mains Overvoltage Fault":

1. Immediate Actions:

   • Stop Operation: If the drive is running, stop it immediately to prevent potential damage to the drive or connected equipment.
   • Reset Error: Attempt to reset the error using the drive’s control panel. This may clear temporary issues.

2. Inspect the Power Supply:

   • Voltage Check: Measure the supply voltage using a voltmeter to ensure it is within the specified range for the drive. Compare the measured voltage with the drive’s rated input voltage.
   • Power Quality: Check for fluctuations or surges in the power supply. These can be caused by issues such as unstable power sources or equipment starting and stopping.

3. Verify Electrical Infrastructure:

   • Wiring and Connections: Inspect the wiring and connections from the power source to the drive. Ensure all connections are secure and properly terminated.
   • Circuit Breakers and Fuses: Check for any tripped circuit breakers or blown fuses in the power supply circuit. Replace any blown fuses with ones of the correct rating.

4. Check Drive Settings:

   • Input Voltage Range: Ensure the drive’s input voltage range settings are correctly configured for the supply voltage.
   • Overvoltage Thresholds: Verify that the overvoltage protection settings are set appropriately for your application.

5. Inspect External Devices:

   • Power Conditioning Devices: Ensure any power conditioning devices (e.g., surge protectors, voltage regulators) are functioning correctly.
   • Transformers: If a transformer is used, check for issues such as incorrect tap settings or malfunctioning components.