Carel Hecu CO2, Руководство пользователя

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42
ENG
Hecu
C O
2
+0300085EN rel. 2.2 - 07.05.2019
Timer
Defrost
UNIT 1
UNIT 2
UNIT 3
Defrost
Defrost
t
dP(1)
d5(2)
d5(3)
dP(2) dP(3)
OFF
ON
OFF
ON
OFF
ON
OFF
ON
Fig. 7.l
Key
dP Maximum defrost duration
UNIT 1…3 Unit 1…3
d5 Defrost delay from digital input
t Time
5 = door switch (see parameter A3)
6 = remote On/Off
The digital input can also be programmed as a remote ON/OFF switch.
When the controller is OFF:
•
the temperature is displayed alternating with the message "OFF"; the
internal timer related to parameter dI is updated. If dI expires whe the
unit is OFF, the controller runs a defrost when restarting;
•
the auxiliary relays set as AUX and light remain active, while the other
auxiliary outputs are deactivated;
•
the buzzer and alarm relay are deactivated;
•
the controller does not perform any control actions, defrost, continuous
cycle, temperature alarms or any other functions.
When the controller restarts, all of the functions are reactivated, except
for:
•
defrost on start-up;
•
fan delay on start-up.
Note: ON/OFF from external digital input has priority over the
keypad and supervisor input.
7, 8, 9, 10, 11 = Do not select
12 = Auxiliary output
By setting H1/H5 = 2, the corresponding output, AUX1/AUX2, is activated
by the AUX1/AUX2 button or by the digital input, if confi gured. In
addition, a digital input DI1, DI2 or DI3 (set A11, A5 or A9 = 12) can be
used to control AUX1 or AUX2.
In this case, the button and the digital input have the same priority for
activation.
13 = Do not select
14 = Continuous cycle activation
Activation: contact switches from open to closed;
Deactivation: contact switches from closed to open.
15 = Alarm from generic function
Digital inputs DI2 and DI3 can be associated with specifi c alarms using
the generic functions, and can be active when the input is open or closed
(see the paragraph on Generic functions).
16 = start/stop defrost from external contact
Application: an external device is used to start the defrost (on closing
the digital input) and subsequently stop it (on opening the digital input).
When the digital input opens, the dripping time set for parameter dd
must then elapse.
Note:
•
if following the start of the defrost, the digital input does not open
before the time dP1 elapses, the defrost will terminate by time and
alarm Ed1 will be displayed (defrost ended by timeout.
•
opening the digital input does not start the defrost only if the
defrost probe (e.g. B2) temperature is greater than dt1 (end defrost
temperature on main evaporator).
•
if a separate defrost is confi gured on two evaporators (d13=1) and
start/stop defrost from external contact is set, both evaporators are
defrosted at the same time.
17 = serious alarm
Application: external alarm that causes the immediate deactivation of the
outputs on UltraCella (except those confi gured as a light/alarm) so as to
prevent a dangerous situation. This can be used, for example, to stop the
compressor following activation of an external protection device.
Activation of the alarm causes:
•
shows the message on the display (‘SA');
•
activates the buzzer, if enabled;
•
activates the alarm relay, if selected;
Involves the following actions on the actuators:
•
immediate deactivation of all the outputs (relays), except for those
confi gured as lights and/or alarms.
Note: if more than one digital input is confi gured as a serious
alarm, the alarm is generated when one of the inputs opens.
Type of defrost
UltraCella can manage the following types of defrost, depending on the
setting of parameter d0:
0. heater by temperature;
1. hot gas by temperature;
2. heater by time:
3. hot gas by time.
For further explanations, see chap. 6.
Par. Description Def Min Max UOM
d0 Type of defrost
0 Heater by temperature
1 Hot gas by temperature
2 Heater by time
3 Hot gas by time
0 0 3 -
dt1 End defrost temperature, main evaporator 4.0 -50.0 200.0 °C/°F
dP1 Maximum defrost duration 30 1 250 min
Evaporator fans
During the dripping time (parameter dd > 0) and post dripping time
(parameter Fd > 0), the evaporator fans are always off . This is useful to
allow the evaporator to return to normal temperature after defrosting.
The evaporator fans can be forced on during control (parameter F2) and
during defrosts (parameter F3). See chap. 6.
Par. Description Def Min Max UOM
dd Dripping time after defrost (fans off ) 2 0 30 min
F2 Evaporator fans with compressor off 30 0 60 -
F3 Evaporator fans during defrost 0/1 = on/off 1 0 1 -
Fd Post dripping time (fans off ) 1 0 30 min
Light management
The light can be managed:
•
by the door switch (if A3 = 0) and/or light button;
•
only by the light button.