Lauda Integral XT 150, Operating Instructions Manual

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Integral XT
98
Starting up
YAWE0028 / 24/06/2016
B) Setting the master controller (external controller):
Experience has shown that the setting of the master controller demands much more time than the set-
ting of the internal controller for a pure outflow temperature control. Many days may be necessary for a
difficult control circuit.
1. Alter the setpoint by 5 °C (5 K setpoint step change) and record the outflow temperature and the
external temperature for a sufficient length of time (approx. 20-40 min).
2. If the external temperature oscillates (> 0.1 K), then reduce Kpe until the oscillation dies away.
Always wait a sufficient length of time between the changes (at least 2 oscillation periods).
3. +20 K setpoint step change, await transient response;
-20 K setpoint step change, await transient response.
4. Assess transient responses:
– if an overshoot is to be reduced, then slowly increase Tve (until about 90 % of Tne ),
– vice versa, reduce Tve to about 60 % of Tne,
– in doing this, adjust Tde . Tde = 20 % of Tve,
– continue at 3) after each change: Carry out and evaluate ±20 K setpoint step changes.
5. If the response takes too long, then Tne can be reduced. Similarly reduce Tve , Tde as a per-
centage. Reduce Kpe to 150...200 % so that the system oscillates. Then continue from Point 2.
6. If the tendency to oscillate increases without the overshoot being acceptably reduced,
a) Kpe can be slightly reduced; continue with Point 3,
b) is a larger time constant need to be chosen: Kpe to 150..200 % so that the system oscillates.
Then continue from Point 2.