Valve control in STEP7

hi what working file zip you?

I download your zip and unzip , am not can using file .

what do working in the step7?

I have question you and an example for PID control.

in the example have a tank water , a flow meter ( scale flow) , valve controller.

always flow meter show 4 liter and tank fill water see the 4 liter or tank starting low water few more open

valve control and full water tank few close valve control .

two method  always see flow 4 liter.

you can do write program with LAD in the step7.

thankyou 

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Split from Totalzer problem inOB35
And Using Double Float (64-Bit Real) in S7-300/400 - Library with functions

Hello dear friend thanks for replying to all this question.
Totalizer file I downloaded and I said I did all the steps but this warning is shown.

open project>browse>file totalizer........no working and see warning and you see pic me.

But the project the project practice were to simulate plc, as the picture showed a tank and a solenoid valve analog work flow 4 to 20 mA and a flow meter the amount of effluent per minute to a value of 4 liters per minute Valve and flow meter shows the tank after the fall in output.

The purpose of this exercise is to always flow in the amount of 4 liters per minute of the show and Valve fits open and closed.

If the reservoir level is reduced and the amount of current passing through the meter rapid decline Valve opens the door to reach the base.

For programming the controller should flow by changing the opening and closing of analog Valve altered to the amount of 4 liters per minute to show.

This practice means that we need:

PLC S-300 or S-400

Level sensor or transmitter level

Valve  4..20 mA

According to a photo that showed the most.
Dear friend if you can in each case to see the video and let me work.
Thank you