A customer at a water plant with a large campus of multiple Micrologix PLCs suffered a power disturbance, and afterward, only two of the PLCs reconnected to the Ignition gateway. Those that reconnected are connected to an unmanaged switch that is also directly connected to the gateway. The others are linked via Ubiquiti wireless gear.
They also have a Red Lion G12 that had no trouble reconnecting to all the PLCs. The driver in the Red Lion has a setting to "Reconnect on Error" that I always enable. I remote accessed the gateway and opened RSLinx Classic on the gateway machine and it was able to "see" all of the PLCs without issue. All I had to do to get everything talking again was to disable each device and re-enable them. They all successfully reconnected.
When the operator called me, he did not say how long the power was out, but there is an automated generator for the whole plant, so I suspect the outage was less than 5 minutes where the UPS backed gateway PC was trying to access PLCs that were not available, likely due to the remote stations having their radios power cycled.
The gateway PC has two NICs, one for the controls LAN and the other for the office network.
Here's a screenshot of what I saw (after I disabled and re-enabled the Backwash PLC and it reconnected).
This may be an opportunity to make an improvement to the Ignition Allen-Bradley Micrologix Driver which I believe is part of Allen-Bradley Driver 7.3.6 (b2026042713)
