The Situation: You’re working with a PowerFlex VFD, and you encounter a fault intermittently. It doesn’t matter if the VFD is running or not; the fault code F073 pops up, indicating “EN Net Loss.” You are able to reset the error and restart the drive immediately, until it happens again. Rockwell Automation suggests that this error signifies that “Control through the embedded EtherNet/IP adapter has been interrupted.”
Options to Consider: When faced with the F073 fault, there are several troubleshooting steps you can take. Here are some suggestions and the solution that worked for me:
- Cycle Power: Sometimes, simply power cycling the drive can re-establish the lost connection.
- Check Communications Cabling: Ensure that all cables are securely connected and not damaged. Swap or replace cables for to troubleshoot.
- Review EtherNet/IP Settings: Double-check the drive’s network settings for any discrepancies.
The Solution: To address the F073 fault without stopping the drive, you can change the PowerFlex parameter #143 “EN Comm Flt Actn” to a value of “Hold Last.” This setting instructs the VFD to maintain its last action until communication is restored, rather than entering a fault state.
Implementing this solution can help maintain your operations without interruption, ensuring that a temporary communication loss doesn’t lead to unnecessary downtime. However, if communication loss lasts longer than a few seconds, this could potentially create a bad situation, where you are unable to command the VFD to stop.
