Siemens LMV51.000B2 - Checking the Control Parameters; Example

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Siemens Building Technologies Basic Documentation LMV5... CC1P7550en
HVAC Products 6 Temperature or pressure controller (internal load controller LC) 13.08.2004
Optimum adaption of the controllers to the controlled system can be checked by re-
cording the actual value during startup while the controlled system is working. The dia-
grams 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