# Range Description Comment
1 Static range Fix up sig-
nal
The regulation is active, but the increase relay will be constantly activa-
ted because of the size of the regulation deviation.
2 Dynamic
range
Up pulse The regulation is active, and the increase relay will be pulsing in order to
eliminate the regulation deviation.
3 Dead band
area
No reg. In this particular range, no regulation takes place. The regulation ac-
cepts a predefined dead band area in order to increase the lifetime of
the relays.
4 Dynamic
range
Down pulse The regulation is active, and the decrease relay will be pulsing in order
to eliminate the regulation deviation.
5 Static range Fix down
signal
The regulation is active, but the decrease relay will be constantly activa-
ted because of the size of the regulation deviation.
As the drawing indicates, the relays will be fixed ON if the regulation deviation is big, and they will be pulsing
if it is closer to the setpoint. In the dynamic range, the pulses get shorter and shorter when the regulation
deviation gets smaller. Just before the dead band area, the pulse is as short as it can get. This is the adjusted
time "PID1 ON time"/"PID2 ON time"/"PID3 ON time". The longest pulse will appear at the end of the dynamic
range (45 Hz in the example above).
Relay adjustments
The time settings for the regulation relays can be adjusted in the control setup. It is possible to adjust the
"period time" and the "ON time". They are shown in the drawing below.
Adjustment Description Comment
Period time Maximum relay time The time between the beginnings of two subsequent relay pulses.
ON time Minimum relay time The minimum length of the relay pulse. The relays will never be acti-
vated for a shorter time than the ON time.
As it is indicated in the drawing below, the length of the relay pulse will depend on the actual regulation devia-
tion. If the deviation is big, then the pulses will be long (or a continued signal). If the deviation is small, then
the pulses will be short.
PERIOD PERIOD PERIOD PERIOD PERIOD
t [sec]
Relay ON
HIGH <DEVIATION> LOW
ONONONONON
AGC 100 Designer's Reference Handbook
4189340766 UK
PID controller (AGC 110 only)
DEIF A/S Page 146 of 152
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