Carel MPXone ACS00CB000010, User Manual

Page: 81 / 108

Ref. Description
T_EVAP Evaporation temperature
LOP
LOP protection
PL3 LOP: alarm delay
Ref. Description
t Time
LOP Protection
Code Description Def Min Max UOM User
User
terminal
PL1 LOP: min saturated evap. temp. threshold -50 -50 50 °C/°F M NO
PL2 LOP: integral time 0 0 240 s M NO
PL3
LOP: alarm delay
0 = function disabled
0 0 240 s S NO
PL1 represents the evaporation pressure, expressed in degrees (saturated), below which the LOP
protection is activated. The protection function is deactivated immediately when the pressure exceeds
this threshold.
PL2 represents the integral constant used during activation of the LOP protection function. This integral
time acts in addition to normal PID control.
PL2 = 0 ==> LOP protection and alarm disabled
PL3 represents the alarm activation delay after exceeding the LOP threshold. When the alarm is activated,
the following occur:
l
Message ‘LOP’ shown on the display;
l
Buzzer activated
The alarm features automatic reset when the evaporation pressure rises above the threshold PL1.
PL3 = 0 ==> LOP alarm disabled.
Manual valve positioning
Code Description Def Min Max UOM User
User
terminal
PMP
Enable manual expansion valve positioning
0/1 = disabled/enabled
0 0 1 - S NO
PMu Manual valve position - 0 600 steps S NO
PMP is used to enable/disable manual positioning of the valve.
l
PMP = 0: manual positioning disabled;
l
PMP = 1: manual positioning enabled.
If manual positioning is enabled, this is used to set the manual opening of the electronic valve. The value
is expressed in steps.
Read-only variables
Par. Description Def. UOM Min Max
PF Valve opening steps (supervisor) - step - -
SH Superheat - K - -
PPU Valve opening percentage - % - -
tGS Superheated gas temperature - °C/°F - -
tEu Saturated evaporation temperature - °C/°F - -
PF: status variable that only displays, solely from the supervisor, the current position of the electronic valve
calculated by the controller. System malfunctions may cause this value to be different from the effective
position of the valve.
SH: status variable that only displays the superheat value calculated by MPXone and used to control of
valve.
PPu: status variable that only displays the electronic valve opening as a percentage.
tGS: status variable that only displays the evaporator outlet temperature read by the corresponding
probe (parameter /Fd).
ENG
0300086EN rel. 1.0 – 04.09.2018
5. Functions | 81