Siemens PLC to Zenon - Variable update time delay in S7TCP driver - Profinet network

Siemens PLC to Zenon - Variable update time delay in S7TCP driver - Profinet network

Hello,

In my project i am using Siemens CPU 319 and in zenon S7TCP driver was used to communicate with PLC in Profinet network. Total 4200 PLC variables are created in Zenon. Out of 4200 variables 1200 variables are used as permanently read variable.

I am getting a delay in variable update in zenon. Whenever a string value changed in PLC and it is getting update in Zenon after 7 SEC and this delay is not consistent. Some times it is taking more than 30 SEC to update the variable values. I have tried with Global update time as 1000 ms and the status was same. If i tried with priority in variables as normal with 500 ms then the status was good and for highest priority with 100 ms also working fine.

If i tried the same PLC network with less zenon variables then the status was good. If variable was increased then the update timing is varying in zenon.

So Please clarify me on below points,

1. How to set/adjust the Global update time or priority for variables to poll the data from PLC faster as possible for more than 5000 tags. Expected update time would be 1 sec.
2. Is there any relation between permanently read variable setting and tag update with priority setting.
3. If i create a multiple S7TCP driver instance for a same PLC then it will update the variables faster then a single driver instance. Please confirm.


Regards,

Dhanapal









This is a migrated post! Originally posted on 25.08.2018 by user Dhanapal. Please be aware that information can be outdated.