Ignition Kepware communication delay

Hello people, I am having a configuration as TIA portal - Kepware - Ignition 8.1 Perspective. All my tags are healthy, communication is established and data is reading as well as writing. I am facing an delay issue in this configuration, like when I write on any tag in Ignition or from Ignition to TIA through Kepware, it is taking much longer time to update that tag, almost 20 - 30 secs. If I read/write values on memory tags in Ignition or Simulate PLC in TIA portal, it is acting very normal, the response time is fast within the respective software. All my settings are as per required settings, scan time of Kepware is in msec. I am unable to figure out what is the issue with this.
I am using License versions of every software. Please guide through this.

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Sounds like your PLC is overloaded with comms. You should check for delays on tag reads, too.

Thanks for your response, We have configured PLC on only one comms, there are no other dummy comms. Also for the tags, we have set 500msec scan rate, below that we have seen data lost, like we tried keeping 100msec, but found we loosing some data transfer. Still couldn't figure out what is wrong in the setup.

I'm not a Siemens guy, but if you're able to go slower, try going slower. You may also want to check how many tags you're scanning at your various tag scan groups. In the status of for OPC clients in Ignition you should be able to see how many tags are being read at each tag scan rate. If you're reading them all at 500ms, is that speed necessary on all tags or only some? Usually there are tags you need at faster rates because they're either live I/O or PLC calculated values, and some (or many) that rarely change that can be read at slower rates (like alarm setpoints, configuration values, etc).

Thanks for your response, I am trying to grouping the tags and setting up less scan time for that particular group in kepware. Hope so this will work..!!

i think had this issue, is about channels in kepserver, the more channels the better. i put arround 50-200 tags in each channel and no more delay. i was experiencing arround 20secs delay, my plcs were in the same channel (arround 20plc) at default scanclass, now works like intended.

More channels doesn't always mean better comms. The general best practice for local PLCs not across a slow cellular network or anything is to put each PLC in its own channel. Adding more channels connecting to the same PLC can make things worse, as each channel creates a new connection that is now competing for CPU cycles on the PLC for comms, or overload comms on the PLC depending on how much that PLC can handle. On the other hand, grouping PLCs together on a common channel is usually only done for slow/high latency connections as to not over-saturate the connection, or for something like Modbus 485 where only one device should try to communicate at a time, so grouping them in a channel forces Kepware to cycle through them in order. You'll also want to turn on auto-demote for any of these so if a device goes offline, it will slow down comms until it gets demoted, but won't always slow it down all the time.

sorry i totally meant that but worded it badly, you are right. channel per plc is the key here.