
1.1.2
Reciprocating compressor capacity control
Proportional zone
K
If the process value lies within this zone the step time is calculated
based on the difference between process value and setpoint. The
zone lies symmetric around the setpoint. Furthermore, this value
must always be greater than the value for the neutral zone.
Correction P Zone
K
The "Correction P Zone" value enables the correction of the lower
boundary of the proportional zone in case this boundary lies below
the alarm limit for low suction pressure.
Capazität +min
Capazität +max
Capazität -min
Capazität +min
secs
secs
secs
secs
During increasing or decreasing capacity, the capacity controller
uses a step time to prevent too fast changes in compressor
capacity. This step time is calculated between its maximum and min-
imum value. This calculation is made if the process value is within
the proportional zone only. The larger the difference between proc-
ess value and setpoint the shorter the step time.
Hint!
The minimum step time between capacity steps is always 15 seconds.
The way the step time is calculated illustrated by example in the following diagram.
Operating Manual | Sequence Control for Packages
GSC TP
Parameters
GEA Refrigeration Germany GmbH | E_301510_2 | Generated 17.12.2014
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