11 Ethernet PLCs Fail At Once

Event Year: 2003 Reliability: Likely But Unconfirmed
Country: United States
Industry Type: Metals
Description:

Around 11pm every PLC5 Ethernet controller in our facility lost its memory (11). Processors that were only on DH+ were fine. Furthermore, our GE PLC’s on the network were unaffected. To fix the problem we configured the Ethernet port via the serial port and then we downloaded new programs via Ethernet. All the batteries are good.

Our DH+ PLCs were not affected as well as SLC 505 E’s. The GE PLCs are Ethernet and again did not have a problem. So our problem seems to be with PLC 5/X0 E. We do have a mix of 80E, 40E and 20E processors. We use 2 subnets one for the melt shop and one for the rolling mill.

Two nights in row we lost ALL PLC 5 processors that are on Ethernet.