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6.3.6 Manual valve positioning from the supervisor
PMP EEV - ADV Enable manual positioning of the expansion valve
Code
UOM
PMP
Min
-
0
Max
1
Def.
-
This is used to enable/disable the positioning of the valve, cancelling the activation of any control function
or alarm.
• PMP = 0: manual positioning disabled
• PMP = 1: manual positioning enabled
PMu EEV - ADV Manual valve position
Code
UOM
PMu
Min
-
0
Max
600
Def.
-
If manual positioning is enabled, this is used to set the manual opening of the electronic valve. The value
is expressed in steps for stepper valves, and as a % for PWM valves.
PF EEV - ADV Valve opening steps
Code
PF
UOM
-
Description
Absolute valve position
Min
Max
480
0
ENGLISH
6.3.7 Read-only status variables
Def.
-
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. Not used with PWM valves.
SH Superheat (Parameters modified from version 2.0)
Code
UOM
Po1
K
Description
Superheat
Min
Max
-
-
Def.
-
Status variable that only displays of the superheat value calculated by MPXPRO and used to control of the
valve.
PPU Valve opening percentage (Parameters modified from version 2.0)
Code
PPU
UOM
%
Description
Valve opening as a percentage
Min
-
Max
-
Def.
-
Status variable that only displays the electronic valve opening as a percentage.
tGS Superheated gas temperature (Parameters modified from version 2.0)
Code
tGS
UOM
°C/°F
Description
Evaporator outlet temperature
Min
-
Max
-
Def.
-
A@ /Fd - /FE: Assign advanced probe functions, p. 37
Status variable that only displays the evaporator outlet temperature read by the corresponding probe
(advanced parameter /Fd).
tEu Saturated evaporation temperature (Parameters modified from version 2.0)
Code
tEu
UOM
°C/°F
Description
Saturated evaporation temperature
Min
-
Max
-
Def.
-
Status variable that only displays the saturated evaporation temperature calculated by the corresponding
evaporation pressure probe or read directly by the NTC probe (advanced parameter /FE).
Po6 EEV – ADV PWM expansion valve Ton +Toff
Code
UOM
Min
Max
Def.
Po6
s
1
20
6
This represents the period of modulation (in seconds) for the PWM expansion electronic valve (DC/AC)
only. The opening of the PWM valve is controlled based on the same PID parameters, and refers to the
period Po6 (in seconds) and not the 480 steps representing the maximum opening of the stepper valve.
All the comments made for the stepper valve can thus be applied to the PWM valve, considering these
differences.
6.3.8 Power failure
The electronic valve requires a power supply to be able to open or close. In the event of power failures,
it remains in the current position. Consequently a solenoid valve is required, upstream of each individual
evaporator or master-slave network, to close the circuit and ensure the safety of the installation in the
event of mains power failures. For further information, see the instruction sheet on the electronic valve
(code +050000340). Alternatively, a backup battery can be installed that provides power for enough
time to close the valve. When next restarted, the system is automatically rebooted and resumes normal
control.
6.4 Compressor
This section describe the advanced settings that are useful if MPXPRO is used in non-centralised systems,
that is, where the compressor operating times are managed to avoid sudden starts/stops that may
cause damage. In this section, the compressor/control output is assumed to be connected directly to a
compressor.
“MPXPRO” +030220186 - rel. 2.0 - 07.02.2008
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