Siemens LMV5 Series - Checking the Control Parameters; Example

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Siemens Building Technologies Basic Documentation LMV51... CC1P7550en
HVAC Products 6 Temperature or pressure controller (internal load controller LC) 01.10.2003
Optimum adaption of the controllers to the controlled system can be checked by
recording the actual value during startup while the controlled system is working. The
diagrams below reveal incorrect settings and give hints on remedy.
Here, the behavior of a controlled system of the 3
rd
order for a PID controller is shown.
The procedure for setting the control parameters can also be applied to other types of
controlled systems.
Practical value for «TN : TV» = 4...6.
XP too small XP too great
t
x
w
7550d21/0501
t
x
w
7550d22/0501
Tn and Tv too small Tn and Tv too great
t
x
w
7550d23/0501
t
x
w
7550d24/0501
Optimum setting
t
x
w
7550d25/0501
Checking the control
parameters
Example