Proportional two analog outputs

[dark_jackal7]

I make the english version of program and what I ve done this far.
I need help with networks 14 15 16. Have to put the pid regulation. The input temperature must be the setpoint. So for example if the setpoint is 28 and the current input temperature is 23 the three-way valve starts opening (at 5% the pump starts working) and PID regulation mus ensure to reach the 28. as the temperature is being reached the valve is proportionally closing down.

you have the picture of my process in previous posts.

tnx

 

[Paul B]

I cannot open your project. I get an error saying Windows has to be set to Croatian language. I have set this in Control Panel and rebooted the computer but still get the error. See attached screenshot.

Anybody know how to resolve this?

 

[dark_jackal7]

i had some warnings with some english projects, but it was possible to open it and see what was programmed.

 

[cagliostro]

Hi,

same problem......

I try open your project attached on post#31,after installed Croatian (Bosnia bla bla bla), but nothing change.
Not possible open your project

 

[dark_jackal7]

OB1 cals FC1, OB35 calls FC4. I want to put the pid fb58 block in to the fc4 and do the previously described process.


this way its possible, dont know why is this happening.

 

[cagliostro]

All right,

to open the project attached from dark_jackal7 follows this steps.

1)Open the directory where store the S7 project (in my PC the path is C:\Programmi\Siemens\Step7\S7Proj).

2)Now open the whatever project directory.

3)Now open the directory call Global and copy the file call Language.

4)So paste the file in the directory call Global where you dearchive the project attached from dark_jackal7.

That's all

 

[cagliostro]

Dearchive the project and take a look.......
Don't expect that everything solve, read the rungs comment in OB35.



Regards

 

[dark_jackal7]

thank you so much, this is helpful.

 

[dark_jackal7]

I cant get nothing but zero on the output of pid. I tried several combinations but nothing.

 

[cagliostro]

Hi,

Are you sure that the input MAN_ON (bool) is OFF???
Check the value in the DB58.

As the image attached you can see that the PID OUT is not 0.
Anyway I attached the project again, copy the DB58 on your project.

 

[dark_jackal7]

man_on wasnt assigned at all. i didnt catch why wasnt it working, but now it is and thank you very much.

 

[dark_jackal7]

I`ve got the output on PID (fb58) 0...10V (0-27648)and want to turn on the pump when the valve at pid is opened 5% (at 1383).
I tried the move command, tried with fc105, tried sfc20 but no success. It is giving me the wrong number at the output of the move command, so I cant compare it with 5% on the comparator. Any idea?

Thanks.

 

[cagliostro]

Hi,

it's easy to do....

Use the PID out variable call LMN in the FB58.

This is the PID Out scaled in %,you can use directly also the DB58.DBD18 of PID istance DB, so compare this variable with the treshold of 5.0% and use the RLC of compare to activate the flag to start-stop motor pump.
See picture attached.

About your post:

It is giving me the wrong number at the output of the move command

the problem is in rung 4, you are using the variable INT format PID LMN_PER moving in MD55.
Could be correct as solution, but before comparing with the real instruction you must do the data format
conversion from INT to DINT from DINT to REAL as suggest in the picture:

 

[dark_jackal7]

thanks, very instructive post.