Yaskawa · F7 Drive
This fault indicates a loss of serial communication (e.g., Modbus) between the drive and its control system for more than 2 seconds, affecting parameters like H5-04 and H5-05. The drive will execute a programmed stopping method, becoming unresponsive to external commands. Prolonged communication loss can lead to process interruption and potential safety hazards if the drive is not properly controlled.
Click steps to track your progress.
Verify the operational status of the master controller (PLC/HMI) and its communication port, ensuring it is powered on and actively sending commands to the drive.
Inspect the network cable and connectors between the drive and the master for physical damage, looseness, or intermittence, using a cable tester if available.
Adjust parameter H5-04 (Communication Timeout Detection Time) to a longer duration (e.g., 5-10 seconds) to account for expected network latency or intermittent traffic.
Confirm that parameter H5-02 (Communication Node Address) on the drive matches the address configured in the master controller's communication settings.
Use network diagnostic tools to monitor the serial communication bus (e.g., Modbus RTU traffic) for errors, delays, or periods of inactivity from the master.