Technische Alternative UVR 63H, Руководство по эксплуатации и установке

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54
Stability problems
The speed control contains a "PID controller". It guarantees exact and fast matching of the
actual value to the set value. In applications such as solar systems or load pumps the pa-
rameters of the factory setting guarantee stable behaviour. In special cases though compari-
son is imperative.
Set value = desired temperature Actual value = measured temperature
PRO 5 Pro
portion part of the PID controller
5
. It represents the reinforcement of the devia-
tion between set and actual value. The speed is changed one increment per 0.
5
K
deviation from the set value. A high number leads to a more stable system but also to
greater deviation from the temperature set.
(fs = 5) Setting range: 0 to 100
INT 5 Int
egral part of the PID controller
5
. Periodically adjusts the speed relative to the
deviation remaining from the proportional part. For
1
K of deviation from the set value,
the speed is changed one increment every
5
seconds. A larger number makes the
system stable, but the adjustment to the set value is slower.
(fs = 0) Setting range: 0 to 100
DIF 5 Dif
ferential part of the PID controller
5
. The faster a deviation between set and actual
value occurs the greater the tendency to short-term "overreaction" in order to achieve
compensation as fast as possible. If the set value deviates at a speed of 0.
5
K per
second, the speed is changed by one increment. Higher values provide
a more stable system but adjustment to the set value is slower.
(fs = 0) Setting range: 0 to 100
The parameters PRO, INT, and DIF can be determined by a test:
The pump should be running in automatic operation with the system ready for operation
with the appropriate temperatures. With INT and DIF set to zero (= switched off), PRO is
reduced from 10 every 30 seconds until the system becomes unstable i.e. the pump speed
changes its rhythm; it can be read off in the menu under command ACT. The proportional
part at which instability begins is noted as P
krit
, with the duration of the oscillation (= time
between the two highest speeds) noted as t
krit
. The correct parameters can be determined
with the following formulae.