Autostart In Pump Down; Continuous Cycle; Anti-Sweat Heater - Carel ir33+ small wide User Manual

6.5 Autostart in pump down

As seen in the previous paragraph, on reaching the set point, the
controller closes the pump down valve and then the pressure switch
signals low pressure. If, due to valve tightness problems, the pressure
switch is activated again, the compressor can be restarted by the
Autostart function.
Par. Description
c9 Autostart in pump down
0 = Disabled
1 = Pump down whenever closing pump
down valve & following low pressure switch
activation with no cooling demand
ON
CMP,
FAN
OFF
ON
VPD
OFF
ON
PRESSURE
SWITCH
OFF
ON
AtS
OFF
Sv
St
Key
CMP, FAN Compressor, fan
VPD Pump down valve
Pressure switch Pressure switch
Sv Control probe
Note:
•
in the compressor autostart function, the protection times c1 and c2
are applied, but not c3;
•
The message "AtS" is reset automatically when the next pump down
cycle terminates correctly.
Important: in the event of "Pd" alarms, the autostart function is
deactivated.

6.6 Continuous cycle

For information on activating the continuous cycle from the keypad, see
chapter 3. The value of parameter cc must be >0. During operation in
continuous cycle, the compressor continues to operate, independently
of the controller, for the time cc, so as to lower the temperature even
below the set point. The continuous cycle is stopped after the time "cc"
or when reaching the minimum specifi ed temperature, corresponding to
the minimum temperature alarm threshold ("AL"). If, after the end of the
continuous cycle, the temperature falls by inertia below the minimum
temperature threshold, the low temperature alarm signal can be ignored
by suitably setting parameter c6: alarm bypass after continuous cycle.
Def Min Max UOM
0 0 1
Tab. 6.e
t
c7
c7
Fig. 6.j
St Set point
c7 Maximum pump down time
t Time
AtS Autostart in pump down
Par. Description
cc Continuous cycle duration
c6 Low temperature alarm bypass time after
continuous cycle

6.7 Anti-sweat heater

When the unit is powered on, the compressor is activated in cooling
-
mode and the AUX and light outputs are disabled until the control probe
measures a value less than St + Hdh. The aim is to prevent the light or the
heater connected to the AUX output from adding heat and contrasting
the work done by the compressor. When the function is active, the display
shows the corresponding icon, fl ashing.
Par. Description
Hdh Anti-sweat heater off set
0 = anti-sweat heater function disabled (°C)
32 = anti-sweat heater function disabled (°F)
The following example refers to the confi guration where Hdh = 2 and St
= 0, with activation of the auxiliary output (H1 = 2)
Key
CMP, FAN Compressor, fan
AUX Auxiliary output
St Set point
t Time
ir33+
Note:
•
when alarms "HI", "IA", "dA", "CHt", "EE", "EF" , " rE" are active of the controller
is OFF, the anti-sweat heater function is still enabled;
•
at the end of the anti-sweat heater function, the outputs confi gured
as light or auxiliary can be controlled by the user from the keypad,
supervisor or digital inputs.
•
if AUX1 or AUX2 is confi gured as a light or auxiliary output at power on,
the output retains the same status as when previously powered down.
If the anti-sweat heater function is activated, this is no longer true: the
output at power on remains OFF while the function is active. When
the control temperature (virtual probe) reaches the value of "St+Hdh",
the function ends, activating the light output and auxiliary output
irrespective of their status when previously powered down.
31
Def Min Max UOM
0
2
Def Min Max UOM
0
ON
CMP,
FAN
OFF
ON
AUX,
LIGHT
OFF
Sv
St+ Hdh
t
Fig. 6.k
LIGHT Light
Sv Virtual probe
Hdh Off set

ir33plus +0300028EN rel. 1.1 - 05.05.2017
ENG
0 15 hour
0 250 hr/
min
Tab. 6.f
-50 200 °C/°F
Tab. 6.g