Hello every body.

I'm new in the forum and I hope you can help me, and maybe som day I can help som people.

I've a problem programin a floor heating control.

I've 2 sensor PT100, one for the temperature of the water (AI3) and another for the outside temperature (Ai4).

And the actuator is a siemens valve 0-10V

I want to do a PI regulation of the water temperature depending of te outside temperature, when I have 0ºC outside I want 45º at the water flow, and the the I want to rest the outside temperature to the flow temperature for higher outside temperatures.

For examples if I've 5ºC outside I want 40ºC at the flow, ....

To conditioning the outside temperature and use it as the SP input in my PI regulator, I use 

Ok, I can do this with a simulation all is perfect, but when I program my logo, the value the value given by the analogic amplifier (SP conditioning) is the offset no the real AX. But in the simulation it's ok

The most strange is that in the graphic, the value of the SP is the correct value, but not in the litle menú on the picture of the bloc, and the valve always searched the position for 45ºC 

(The valve works correct because if I put 35ºC in te SP input then its go to 35ºC)

I hope you can help me.

I attach a picture of my diagram (simulation).

Thanks

Test your program in online test.In this test view AQ online in logo

Hi, I did it, my problem is when I program the logo and I test in online. The value than AX of the SP conditioning takes in online mode (when the logo is running) is the value I program for the offset not the real AX (AX*gain+offset). And this AX value is what I connect to the SP input of the IP regulator.

This ocurrs only in online mode, in simulation the value of AX its correct.

Thank you very much.

Can you please send me your program I would like to try to solve this for you !!

kind regards Gerry

Ok.

Here you have my program

Thank you.