For i = 0 To 23

Sum()

Next

sub Sum()

Dim V1

Set V1= HMIRuntime.Tags("Var")

V1.Value = V1.Read + 1

V1.Write ,1

End Sub 

The Var finaly value should be 24 but always is 1

Some one can help me?

Thanks a lots!

 If I use Msgbox and delay in implementation sometimes the result varies but i don't understand why...

FranCP

Good I am working with WinCC for Scada and I have created a global variable to make a sum and read and save the values in this varaible but for some reason the write does not execute when it should.

The code is as follows:

For i = 0 To 23

Sum()

Next

sub Sum()

Dim V1

Set V1= HMIRuntime.Tags("Var")

V1.Value = V1.Read + 1

V1.Write ,1

End Sub 

The Var finaly value should be 24 but always is 1

Some one can help me?

Thanks a lots!

No one can help me?

 Hi, 

Michael, yes! This was the problem, I read the manual but I didn't quite understand the READ(1).

Thanks, a lot!

Michael K

Hi,

Try to look in the manual:

WinCC V7.5 SP2 WinCC Information System

and search for
VBS136
Here you will find an example of adding a value to a tag.

But your example looks very ineffective. You should store the intermediate value in an internal vbs variable and then write the final value to back to the tag when the calculation is done.

Also search the manual for
VBS137
Here you see an example of "Direct reading". This is probably .read - method you should use.
What you are probably seeing is that vbs is caching the read/writes and therefore you continuously read the same value in each loop.

I hope this helps.