Carel iJW handleiding
Handleiding
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iJW +0300103EN rel. 1.1 - 31.03.2025
Index
Start defrost
The events that activate a defrost are shown in the table.
Event Defrosting
Interval between defrosts expired Dependent on enabling (dI > 0)
Time band Dependent on enabling (time bands set) and presence of the RTC
Compressor running time Dependent on enabling (d10>0 and Sd<d11)
Start-up Dependent on enabling (d4=1)
At each compressor start Dependent on enabling (Sd < d11)
Digital input Dependent on enabling (DId > 0)
Supervision Always
Keypad/Direct function Dependent on the presence of the button/enabling of the direct function
App/Commissioning tool Always
Opening the door Dependent on enabling (DcL > 0)
Tab. 7.i
Start defrost
The iJW controller can manage the following types of defrosts, based on the setting of parameter d0:
1. heater (placed near the evaporator) by temperature;
2. hot gas by temperature;
3. heater by time;
4. hot gas by time;
5. heater by time with temperature control.
The details of each type of defrost are illustrated in the following paragraphs.
If defrost by temperature is selected, it is performed only if the value read by the evaporation temperature probe Sd is lower than
the defrost end value (dt1 and dt2) or has an error. This also applies when there are two evaporators.
For heater defrosts:
• fi rst the time d15 elapses (if confi gured);
• the compressor stops (performing pump down, if enabled);
• the main and secondary evaporator defrost relays are activated to switch on the heaters.
During hot gas defrost:
• fi rst the time d15 elapses (if confi gured);
• then the compressor stops;
• the time dHG/2 elapses;
• the main and secondary evaporator defrost relays are activated to open the hot gas valve;
• the time dHG/2 elapses;
• the compressor starts;
Notice: if parameter dHG has a value other than zero, pump down is not performed during hot gas defrost.
Notice: if the control temperature is lower than the low temperature alarm threshold (parameter AL or ALA), the compressor
cannot start and therefore the hot gas defrost will not be performed. If the temperature falls below the alarm threshold during
defrosting, the compressor will stop immediately.
End defrost
The defrost ends by temperature when the values set by parameters dt1 and dt2 are reached, or by time, when the values dP1
and dP2 are reached, based on the setting of parameter d0.
If defrost by temperature is selected, the defrost probe Sd needs to be installed; the defrost ends when the probe Sd measures
a value greater than the setting of dt1 or by timeout after the maximum time dP1 has elapsed; in this case, based on the setting
of parameter A3, Ed1 is displayed. If set to end by time, the defrost ends after the time dP1.
The heater defrost by time with temperature control (d0=4) activates the defrost output only if the evaporator temperature Sd
is less than the value of parameter dt1, and ends after the time defi ned by dP1. This function is useful for energy saving and to
avoid excessively heating the evaporator.
For units with two evaporators, the defrost ends when both evaporators have reached the end defrost condition. If one evap-
orator ends defrosting (by time or by temperature) before the other, the corresponding defrost relay is de-energised, while the
compressor remains in the status required by the defrost.
For hot gas defrost, when the defrost ends:
• the compressor stops;
• the time dHG/2 elapses;
• the main and secondary evaporator defrost relays are deactivated to deactivate the hot gas valve.
• the time dHG/2 elapses;
• the compressor starts;
At the end of the defrost, the controller can activate the dripping phase (if dd>0), during which the compressor and the fans are
off , followed by the post-dripping phase (if Fd>0), during which control resumes with the fans off . If the defrost ends prematurely
(e.g. interrupted by keypad/BMS), the dripping and post-dripping phases are skipped.
The type of display on the user terminal during defrosting can be selected by setting parameter d6.
Notice: high temperature alarms can be disabled after defrosting by setting par. d8.
Bekijk gratis de handleiding van Carel iJW, stel vragen en lees de antwoorden op veelvoorkomende problemen, of gebruik onze assistent om sneller informatie in de handleiding te vinden of uitleg te krijgen over specifieke functies.
Productinformatie
| Merk | Carel |
| Model | iJW |
| Categorie | Niet gecategoriseerd |
| Taal | Nederlands |
| Grootte | 14964 MB |
