Lauda L 100, Operating Instructions Manual

Page: 30 / 48

In the case shown here, the preset I-component is too large
(parameter Tn too small, Tn must be increased). The I-component
integrates the control deviation until it becomes 0. If integration
proceeds too rapidly, the actuating signal, i.e. the output signal of
the controller, is too large. As a result, the actual value fluctuates
(fading) around the target value. The hold-back time (parameter
Tv) should be adapted using the formula: Tv = Tn x 0.75 adapted.
The actual value increases relatively sharply towards the specified
target value. The proportional area settings seem to be correct. If
the control deviation becomes smaller, the actual value
approaches the target value much more slowly. The integration
component (I-component) must compensate for the drastic reduc-
tion of the proportional component (P-component). In this case, the
I-component is integrated too slowly. The parameter Tn, which
specifies the integration interval, must therefore be reduced. The
hold-back time (parameter Tv) should be adapted using the for-
mula: Tv = Tn x 0.75.
5.10.2 Overview of control parameters
The internal control compares the set temperature T
set
with the
bath temperature T
int
and calculates the actuating signal, i.e. the
measurement used for heating or cooling.
Designation Abbreviation Unit
Proportional range Xp K
Adjustment time Tn s
Hold-back time Tv s
Attenuation time Td s
If Tv manual/auto is set to auto , Tv and Td cannot be
modified. In this case, they are derived with fixed factors
of Tn.
The following parameters may also influence the control:
 Temperature limits: Til and Tih
Fig. 14: Control parameters Tn and Tv
too small
Fig. 15: Control parameters Tn and Tv
too large
Operation
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