48
ENG
mpxone +0300086EN rel. 2.2 - 13.11.2023
Functions
ON/OFF (par. ON)
Parameter ON is used to switch the controller ON/OFF. If there is a digital input configured as local ON/OFF (switch), this has
higher priority than the supervisor command or parameter ON.
Code Description Def Min Max UOM User User terminal
P10 ON/OFF command - 0=OFF, 1=ON 101- SYES
In this operating mode, the display shows the standard display, alternating with the message “OFF”.
When OFF, the following are possible:
• access the parameters on the user terminal;
• activate remote ON/OFF;
• display the probe alarms (rE, E1, E2, E3, etc.) and errors EE, EF, Etc, Edc, alternating with the message OFF.
When OFF, the following alarms are reset:
• high and low temperature;
• open door alarm (dor);
• valve (LSA, LowSH, MOP).
Double thermostat
The double thermostat function is activated by setting parameter rd2> 0 and selecting mode AND or OR logic mode (parameter
db1). It is used to automatically adapt, that is, without changing the set point and without an external signal, control of the unit
based on a change in compressor load, especially when switching from day to night and vice-versa. In fact, at night the show-
case curtains are closed, there is less heat exchange with the surrounding air and the compressor works less.
To do this, two set points and two differentials are defined:
• St and rd, associated with the outlet probe;
• St2 and rd2, associated with the intake probe.
Code Description Def Min Max UOM User User terminal
St2 Intake probe set point with double thermostat 50 r1 r2 °C/°F S NO
rd2 Set point St2 differential with double thermostat
0.0 = function disabled
0 0 99.9 °C/°F S NO
db1 Double thermostat function logic
0/1 : logical AND/logical OR
001- MNO
The control request occurs:
• when this is active on both probes, as if there were two thermostats in series, when db1 = 0.
• when one of the probes signals the request, as if there were two thermostats in parallel, when db1 = 1
Sr
Sm
Cooling
AND
300086_061_R01
Sr
OR
Sm
Cooling
300086_062_R01
Sm
rd
St
ON
R
OFF
300086_063_R01
Sr
rd2
St2
ON
R
OFF
Ref. Description
Sm outlet probe
Sr intake probe
R control request
rd differential for St
rd2 differential for St2
Fig. 5.j Fig. 5.k
Below is an example of the temperature trend on a vertical showcase during the day and at night.
t
T
night day
Sr
Sm
Sv=(Sm+Sr)/2
-15...-17 °C
-19...-21 °C
-22 °C -21...-23 °C
-16 °C
-12...-14 °C
300086_071_R01
Ref. Description
Sm outlet probe
Sr intake probe
T temperature
Sv Virtual probe
t time
Fig. 5.l
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