ECKELMANN VS 300 - High Pressure Monitoring

Function of VS 300
43
Doku-Version 2.05 - Firmware 2.10 - 15. September 2017
4.4.1 High pressure monitoring
High pressure is detected in the high-pressure line by a continuous transducer with current output. When high
pressure rises to a definable limit t
c max
(Parameter S265), the first stage is unloaded immediately on exceeding
the t
c limit
regardless of the number of compressors running. Additional stages are unloaded after the basic un
load time has elapsed. This continues until pressure drops to a level below the set limit or a definable number of
compressors remain running.
The number of compressors remaining running after exceeding t
c max
can be defined (Parameter S277). The
default value is a function of the number of compressor stages and must always be redefined following first start
or after chaning the number of compressors. The following table shows the default as a function of number of
compressor stages:
No. of compressor stages Default: No. of compressor
stages in HP fault
1 - 2 1
3 - 5 2
6 - 7 3
8 - 10 4
11 - 12 5
When all compressors are working, unloading of the first compressor takes place without delay. An exception is
heat recovery (HR) mode.
Compressor unload does not take place in HR operating mode. No additional compressor is loaded when the
pressure limit is attained, regardless of any demand for additional load.
Control algorithm
HP monitoring
Limit HPS cutout
Limit HP cutout
Limit comp. dis
able
Limit comp. en
able
Tim
e
Compressor
enable
not dis
abled
Comp. disable
high pressure
t
c
ZNR. 51203 62 630 E0
High HP alarm is generated after a definable delay if the limit set for Disable Comp. (Parameter S225 / S265) is
exceeded. Alarm priority can be defined. No alarm is generated in heat recovery mode. No additional capacity
stages are loaded when a HP alarm is active.
The High HP alarm and compressor disabling are not reset until pressure drops below the level set for Enable
Comp. (Parameter S226 / S266).