Siemens AVS75.39 Series User Manual page 140

Precontrol of mixing
valve
Mixing valve boost
Actuator: running time
Mixing valve Xp
Mixing valve Tn
140 / 239
Siemens
Building Technologies
Line no. Operating line
5120 Mixing valve boost
5124 Actuator running time
5125 Mixing valve Xp
5126 Mixing valve Tn
To ensure proper mixing valve flow temperature control, the flow temperature must
be higher than the demanded setpoint of the mixing valve flow temperature. The
set value is added to the request.
Setting the running time for the actuator used with the mixing valve.
By setting the right proportional band Xp for the mixing valves actuator, the control
behavior of the actuator is matched to those of the plant (controlled system).
The proportional band Xp influences the controller's P-action.
The P band Xp is the range by which the input variable x (controlled variable) must
change to adjust the output variable y (manipulated variable) throughout the entire
positioning range. The smaller the value the greater the jump. The illustration
depicts the reciprocal value 1/Xp = Kp.
By setting the right integral action time Tn, the control action of the mixing valve's
actuator is matched to the behavior of the plant (controlled system).
Tn influences the controller's I-response.
It is the required of the I-portion to undertake the same manipulated variable
change at the given input signal (controlled variable), as immediately provided by
the P-portion. The smaller the Tn the larger/faster the slope.
User manual RVS43.345
The settings in detail
CE1U2354en_021
2013-09-02