Slow OPC Connect with PEC3
Since we have replaced a PEC2 with PEC3 for an existing 800xA Application, the OPC Connection for the PEC3 has a very low performance. (HMI has red Cross from time to time). With the other PEC2 Controller, there aren’t any OPC Problems.
It takes also very long for downloading. PEC3 needs about 3times longer then a PEC2. (waiting on “Sending domains”)
With the afwapplogviewer I calculated about 3528 OPC Tags/s over the whole System (14 PEC2 and 2 PEC3 (both with slow OPC performance). Is there also a possibility to check the Performance for only one Controller?
Where there any network changes for the PEC3? We got a new FPGA and Controller Archive from the Developers. I didn't change anything else. Unfortunately, the PEC Guys don’t really know the CIT area.
See the Configuration in the Attachment.
Do you have any other ideas?
Thank you for helping.
System: 800xA 5.1FP4, 1 redundant Connectivity, 16 PEC Controller. Cyclic Load PEC3 55%
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If the same OPC server handles PEC2 well but PEC3 bad it sounds like the problem is between the OPC server and the controller.
How many MMS/s are you pulling through your controllers (CBM->Remote System->Show MMS Connections will tell)? Does PEC3 exceed PEC2 figures?
55% Cyclic load is OK, but with too many MMS transactions the TotalSystemLoad will soon reach above 95 or even up to 100% and that could explain your problems.
I count to about 100 MMS/s from the second attachment - this should not be a problem for a fast PEC, but I only have experience with regular AC800M:s. The TotalSystemLoad should not exceed 90% for regular AC800M.
Another possible problem is network disturbances - can you check the error counters in the switch connecting the PEC3? Do you see a lot of collision (measured as % of total sent telegrams) or other errors (CRC, lost packets, etc)?
What link speed & duplex have been chosen? Can the PEC do 100 FULL duplex? At FULL duplex there should be no errors at all. At HALF up to 5% collisions (measured as % of total sent telegrams) could be OK. Have the switch negotiated 100 FULL and the PEC maybe 100 HALF or vice versa (then try disabling auto-negotiation and set the speed & duplex manually on both sides)?
Does the PEC controller log tell what duplex its using? Does it agree with the switch? An asymmetric speed & duplex setting often causes "Late Collisions" in the ethernet statistics and performance will be significantly less than expected.
Thank you for helping!