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The data inside this manual are not binding and they can be modified by the manufacturer without notice.
All rights reserved.
NPC 280 - 400
8 . 3
C o m p r e s s o r o p e r a t i o n
The type of thermoregulation can be:
•
Proportional
•
Neutral Zone
:
The Proportional regulation uses as reference the temperature and differential values. When the temperature increases the compressors will start
pregressively. Whne the temperature value decreases under the differential the compressors will stop progressively.
The Neutral Zone regulation uses a further variable: the time. The starting of compressors depends on the temperature value during a certain
time. If during a certain time the temperature measured increases, the compressors will start with a delayed sequence. In this way the number of
compressors in operation is always optimal.
ST07
T
EMPERATURE
ST01
C
OMPRESSORS
OFF
Compr. n°1
Compr. n°2
Compr. n°3
Compr. n°4
Compr. n°5
Compr. n°6
ST01=Chiller Set point
ST07=Chiller Differential
CO 3
CO 4
C
OMPRESSOR
T
IME
Compr. 2 ON
Compr. 3 ON
Compr. 6 ON
Compr. 5 ON
Compr. 4 ON
W
ATER
TEMPERATURE
T
IME
SET
SET+DIFF.
STATUS
NEUTRAL ZONE
NEUTRAL ZONE= Set point (ST01)-[Set point (ST01)+Diff. (ST07)]
Compr. OFF
Compr. 1 ON
CO 3 = Delay between starting 2 compressors. CO 4 =Delay between stopping 2 compressors.
CO 3