Cause : USS/MODBUS setpoint fault comes when no setpoint values from USS/MODBUS during telegram off time. When an inverter displays a "USS setpoint fault," it typically indicates a problem with the setpoint value provided via the USS (Universal Serial Interface) communication protocol.
F72 fault in siemens V20 Drive indicate USS/MODBUS setpoint fault. This means a problem with the setpoint value provided via the USS communication protocol.
Here's how you can address this issue:
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Check Setpoint Values: Review the setpoint values being sent to the inverter via the USS communication protocol. Ensure that the values are within the acceptable range supported by the inverter and are correctly formatted according to the manufacturer's specifications.
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Verify Communication: Check the communication link between the external control device and the inverter. Ensure that the USS communication protocol is configured correctly on both ends and that there are no communication errors or interruptions.
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Inspect Wiring and Connections: Verify that the wiring and connections between the external control device and the inverter are secure and properly terminated. Loose or damaged connections can lead to communication errors or faults.
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Check Parameter Settings: Review the inverter's parameter settings related to USS communication and setpoint handling. Ensure that the inverter is configured to accept setpoint values via USS and that the settings match the requirements of your application.
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Monitor USS Signals: Utilize diagnostic tools or features available in the inverter to monitor USS signals and communication activity in real-time. This can help identify any issues or anomalies that may be causing the setpoint fault.
