OPC tag updating Problem [ update tags on active screen only]

Hello Experts,

I am using Kepware OPC and WinCC 7.3   

Connection is fine.  But OPC tags displayed in active screen are only getting updated. Others just wait. 
If I change screen tags in that screen only are updated.  What to do If I need active updation of all/some tags.  I checked in OPC same time and only the tags in active screen are showing good value. 

By the way: 
WInCC will maintain an active connection, If I run the Quick Client facility in Kepware or If I log these tags in WinCC Cyclically. As the number of tags are more logging all tags unnecessary seems to be a bad idea. 

What should be the reason/limiting factor. Am I doing wrong or something to be enabled?

Thanks :) 

New question published by dahare shiv is split to a separate thread with the subject Problem in updating values through OPC connected devices in WinCC 7.2.

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Min_Moderator

New question published by Alexandr1984 is split to a separate thread with the subject OPC problem updating the value of the tag.

Best regards
Min_Moderator