Average of analog value - S7-300

Hello,
I'd like to obtain average of my analog input value which will be displayed on SCADA. For examplle, analog value should be sampled avery second and and a script/block should create average of value for the last 3 minutes and then store it in other variable.

Is this possible in S7-300? What FB shoudl I use? Is there any predefined Siemens block for that or maybe anoyone faced similiar problem and could help? Any help would be apriciated. thanlks

What you describe is a rolling average filter. I don't think that there is a pre-packaged one available so you will have to write your own unless someone here can volunteer one.

Nick

hope this link will help you,others thing i don't know,

need expert to explain to you.


http://www.plctalk.net/qanda/showthread.php?t=34506

http://www.plctalk.net/qanda/showthread.php?t=75804

http://www.plctalk.net/qanda/showthread.php?t=65902

http://www.spsoftwareautomation.com.au/images/exercise_7_indirect_addressing.pdf