Applies To:
  • CitectSCADA 5.xx

We would get the very occasional temporary failure with Square D through softhub, using ethernet. But recently, some slight change to the Citect project has tipped us over the threshold more regularly. Now the primary server goes off-line every 2 minutes and the standby goes off-line every 10 minutes. There are no driver parameters documented for this driver. What could cause this? 

From the I/O Devices stats, in the Citect Kernel window, View | IODevices, the SQD I/O Devices had a maximum response time of 1.28 secs and its average was 0.25 sec. Therefore this device was regularly just going over the default timeout of 1.0 sec. I increased the driver parameter Timeout=3000, or 3 secs and the Delay=20, or 20msec as suggested, and everything has worked well since.