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5.7.3 Setpoint reduction above medium pressure
The function is only active when
MP const.valve
is set to "
No
" (menu 3-1). This function is deactivated when
ECO operation is running.
A minimum difference between the medium pressure actual value and the suction pressure setpoint is
maintained with this function. The desired pressure difference can be configured with the parameter
Min MP/LP
Diff
(menu 3-3). The suction pressure setpoint is reduced with falling medium pressure that results in loading of
compressors and thus in increase of the medium pressure to the desired pressure level.
5.7.4 Medium pressure maintenance
The medium pressure can be maintained using a
. The
operating mode can be set with the parameter
MP const.valve
(menu 3-1).
Medium pressure maintenance via pressure maintenance valve
If the medium pressure valve is closed (0 Volt control signal) and the medium pressure falls below the medium
pressure setpoint minus a maximum pressure difference, a pressure maintenance valve is activated.
The pressure maintenance valve is switched off again when the medium pressure has reached the MP setpoint
minus 0.5 bar. The maximum pressure difference can be configured.
The following is a graphic representation of the pressure maintenance valve control:
The pressure maintenance valve is switched off for a fast unload. The setpoints for the MP regulation or control
of the pressure maintenance valve
Setp. MP
and
MP dif.
are configured using the menu 3-2-3.
The function is only active when the suction gas sensor
OH-C
is available. As long as MP setpoint
reduction is active due to "
Low Superheat-C
", no setpoint increase due to "
Low Superheat-P
" can take
place.
Summary of Contents for VS 3015 C
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