14.01.2019
53/185
C. Medium pressure setpoint reduction in the case of alarm "
Low Superheat-C
"
This function has priority over the setpoint increase. If the setpoint increase is active, this is interrupted by the
setpoint reduction. If the message "
Low Superheat-C
" is output after a configurable time delay, the medium
pressure setpoint is reduced using a ramp function. The setpoint is reduced using the parameter "
OH-C-Ramp/
m
" until the superheat OHc has increased again to a value greater than "
min.OH-C
". Once this has occurred,
the MP setpoint remains at the changed setpoint for a delay time of 10 minutes.
If the superheat OHc is still greater than the minimum superheat "
min.OH-C
" after expiry of the delay time, the
setpoint is increased again to the MP setpoint using the ramp "
OH-C-Ramp/m
". The MP setpoint is reduced to
the currently calculated to-setpoint plus 3 bar. If the superheat OHc falls below the limit value "
min.OH-C
" within
the 10 minutes delay time, the reduction of the setpoint is continued without taking account of the delay time
"
Del.Min.OH-C
".
The following diagram shows the process graphically:
The function is only active when the suction gas sensor OH-P is available.
Summary of Contents for VS 3015 C
Page 8: ...14 01 2019 8 185...
Page 46: ...14 01 2019 46 185...
