I have a strange performance issue when I connect Ignition to Siemens PLC
The PLC has not an enbedded ethernet port on the CPU , but has a ethernet card ( the CPU is S7 300 315-2AG10-0AB0 )
I definited only a tag , and I connected the PC with ignition directly to the PLC with a ethernet cable ( without swicth, router firewall et etc…) the time to read only a tag are more o less 42ms, of course the PLC has not a program so the time cycles are very fast
If I use the PLC with the ethernet port ebedded to Cpu the time for read one tag is more or less 2ms.
These times are really because I have seen them via wireshark logs, so I can tell that the problem is the ethernet card of the PLC. ( obviously I tried witha new PLC and a new ethernet card but I had the same behaviour)
This behaviour imply if I have only few hundred tags ( 160 with a scanclass of 1000ms) the load factor of communication is very very high and the time for read the tags are very very slow.
The thing is very strange, maybe, are there some setting to make to the ethernet card ?
Do you have any suggestions?
Thank you very much