GTUnit said:
...System network problems may affect the drives.
If it's controlled over Ethernet then you may be losing the Ethernet long enough for the drive to stop but not long enough for it to trigger a "Network Loss" fault.
I don't think this is possible?
While using network control, take EtherNet/IP for instance...
To Start the drive, the controller removes the Stop assertion by writing a zero to the Stop bit. It then writes a one to the Start bit. These writes are to the drive's data table and are done at the configured RPI, and while the connection is healthy.
If the connection times out, then the drive clears the data table and the drive is no longer under the control of the controller. The drive will experience an F073 - "EN Net Loss". If it's configured to Stop on comms loss, then it will Stop.
If the connection does not time out, then there is no comms loss error, the drive will not clear the data table, and the data table values will continue to update at the configured RPI.
So I do not think that any delays or intermittency in the connection, shorter than the watchdog or RPI times, can assert a Stop command, or result in the loss of the Start command.
Having said that...
There is an anomaly with the PowerFlex 525 drives, up to revision 2.02, where they do not clear their data table on comms loss. This is corrected in later revisions.
Regards,
George