[TRNSYS-users] Type 22

[Stefania Agosta]

Good Morning,

I'm trying to use Type 22 (Iterative Feedback Controler) to set 1 of  
the 2 flow rates of a diverting valve.

Rate.1 goes to Tank.1, Rate.2 goes to Tank.2.
What we want to happen is:
Rate.2=1 and Rate.1=0 until the Temperature in Tank.2 reach 80°C,
after that, Rate.1 should be set in order to maximixe the temperature  
in Tank.1 mantaining the temperature in Tank.2 over a certain value,  
let's say 40°C.

I tryed to do that setting:
Setpoint=40
Tank.2 nodal temperature=Controlled variable
Control signal=fraction of flow to outle 2

BUT
-the value set for the fraction of flow to outle 2 does not change  
(=0.75)
-the control signal changes each hour as follows: 0.30 -  
0.45-0.60-0.30-0.45-0.60

Could you please help me find a solution to this problem?

Best regards

Stefania Agosta