Sampling inputs

[thecarb]

Hi all,

 

I have a project with an analog input which connected to a level transmitter. If I directly show the input on the screen, it can change 2-3 times in a second as it is not very stable. So I tried to solve it with sampling with a timer.

 

Timer runs as soon as PLC starts to run. When timer reaches to its "set time", it copies the data on the analog input to a bit and reset itself. On the screen I see the "bit" value. The problem is after some amount of time, lets say 3-4 days, it stops to copying the value and display shows the same value even if the level reaches to full.

 

What do you think? What am I doing wrong?

 

 

Thanks in advance.

[Flex727]

I assume by "bit" you mean an MI operand? Did you try using the built-in filtering available for the analog inputs? There is also a filter function block available to use.

[thecarb]

Yes, "bit" was an MI.

 

I tried to activate the filter from the Hardware configuration but I cannot see the filter section on that screen. I am using V570 and V200-18-E1B. Doesn't have this PLC and I/O filtering?

[Flex727]

Most of the Snap-In modules do not have analog input filtering. Use the filter function block in VisiLogic.

[Henny]

Hello

Besides the filter function it would Also be an option to put si13 as a contact condition

Before your linearisation function.

Your input from the io card is then scaled only one time per second.

Kind regards

Henny