Danfoss AK-CC55 User manual

User Guide
Case/room controller (EEV)
Type AK-CC55 Compact
SW Ver. 2.1x
For refrigeration appliances and cold storage rooms.

Contents
Introduction 5
Portfolio overview 6
Function overview 6
Connectivity 7
Data communication 7
AK-CC55 Compact 7
External display 7
Controller functionality 9
Functions 9
Injection control 9
Adaptive superheat control 9
Adaptive liquid control 9
Thermostatic expansion valve control 10
Temperature control 11
Temperature monitoring 11
Thermostat bands 11
Night setback of thermostat value 12
Temperature sensor types 12
Appliance cleaning 13
Appliance shutdown 13
Defrost 14
Electrical defrosting 14
Simple hot gas defrosting 14
Natural defrost 14
Start of defrost 14
Stop of defrost 15
Defrost sequence 15
Real-time clock 16
Coordinated defrost 16
Melt function 17
Control of two compressors (only with custom set-up) 17
Rail heat 18
Fan 19
Light function 20
AK-CC55 Compact
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Night blind 20
Heating function (only with custom set-up) 21
Digital inputs 21
Forced closing 21
Door contact 22
Display 22
Override 22
Applications 24
AK-CC55 Compact connections and application options 24
Application set-ups and IO connections 25
Product identication 28
AK-CC55 Compact connections 29
Data communication 29
AKV info 29
External solid state relay for rail heat 30
AKS 32R info 30
Coordinated defrost via cable connections 30
External display AK-UI55 31
Connections 31
Operation 33
Operation via data communication 33
Direct operation 33
Operation via AK-UI55 Set 33
Parameter groups when operating via display 35
Get a good start 35
AK-UI55 display menu (SW ver. 2.1x) 37
Thermostat 37
Alarm settings 37
Compressor 38
Defrost 38
Injection control 38
Fan control 39
Defrost schedule 39
Miscellaneous 39
Control 41
DO cong and manual 41
AK-CC55 Compact
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Service 42
Operation via AK-UI55 Bluetooth 44
AK-CC55 Connect menu (SW ver. 2.1x) 45
Start / Stop 45
Conguration 45
Thermostat control 46
Alarm limits and delays 48
Injection control 49
Defrost control 49
Defrost schedules 51
Compressor 51
Fan control 52
Railheat control 52
Light/Blinds/Cleaning control 53
Display control 54
Alarm relay priorities 54
Miscellaneous 55
Advanced 55
Fault message 57
Operating status 58
Product specication 59
Technical data 59
Electrical specications 59
Sensor and measuring data 59
Input and output relay specications 59
Function data 60
Environmental conditions 60
Dimensions 60
Ordering 61
Certicates, declarations, and approvals 62
Statements for the AK-UI55 Bluetooth display 63
Online support 64
AK-CC55 Compact
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Introduction
Application
Refrigeration appliance control with great exibility to adapt to refrigeration appliances and cold storage rooms.
Advantages:
• Control of Thermostatic Expansion Valve (TEV) and Electronic Expansion valve(EEV) applications
• Quick set-up with predened settings
• Easy conguration and service using a mobile app with Bluetooth
• Adaptive Minimum Stable Superheat (MSS) control is performed with lowest possible superheat
• Allows the suction pressure to be raised several degrees
• Adaptive Liquid Control (ALC) can be performed with superheat down to 0 degrees on transcritical CO2systems
with liquid ejectors
Principle
The temperature in the appliance is registered by one or two temperature sensors which are located in the air ow
before the evaporator (S3) or after the evaporator (S4) respectively. A setting for thermostat, alarm thermostat and
display reading determines the inuence the two sensor values should have for each individual function.
The temperature of the evaporator is registered with the S5 sensor which can be used as a defrosting sensor.
In addition to the output of the electronic AKV injection valve, the controller has relay outputs which are dened by
the application setting
Figure 1: AK-CC55 with evaporator, AKV valve and sensor positions
Danfoss 84B3281
S5
S3
S4
S2 P
AKV
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AK-CC55 Compact

Portfolio overview
The AK-CC55 portfolio contains four controllers with dierent functionalities and application settings, as outlined in
the table.
Table 1: AK-CC55 Portfolio
AK-CC55 Compact
AK-CC55 Single Coil
AK-CC55 Single Coil UI
AK-CC55 Multi Coil
Product image
Valve
1 x TXV or AKV
1 x AKV
1 x AKV
3 x AKV
Digital Output
3
5
5
4
Digital input
1 (2)
3 (2)
3 (2)
3 (2)
Analogue Output
1
1
1
1
Analogue Input
5 (4)
6 (7)
6 (7)
6 (7)
Display
1 remote
2 remote
1 remote + 1 Integrated
2 remote
Comm. module
Modbus
Modbus
Modbus
Modbus
Optional comm. module
LON module
LON module
LON module
Function overview
Table 2: AK-CC55 function overview by type
Application
AK-CC55 Compact
AK-CC55 Single Coil
AK-CC55 Single Coil UI
AK-CC55 Multi Coil
AKV - application (electrically operated expansion valve)
x
x
x
0 – 10 V to control external stepper driver
x
TXV - application (thermostatic expansion valve + solenoid valve or compressor)
x
Remote hot gas - application
x
One valve, one evaporator, one refrigeration section
x
x
x
One valve, one evaporator, two refrigeration sections
x
One valve and two evaporators, two refrigeration sections
x
Two valves and two evaporators (same refrigeration section)
x
Three valves and three evaporators (same refrigeration section)
x
Custom conguration of relay outputs
x
x
Two compressors
x
x
Heating function
x
x
Control of air humidity
x
x
Adaptive superheat
x
x
x
Adaptive liquid control
(zero superheat control for transcritical CO2systems with liquid ejectors)
x
x
x
Adaptive defrosting
x
Product sensor
x
Oil recovery
x
RS485 Lon, option (AK-OB55)
x
x
AK-CC55 Compact
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Figure 3: AK-CC55 Compact Figure 4: AK-CC55 Compact with external display.
Danfoss 84B8235
Connectivity
The diagram outlines the connectivity options presented by AK-CC55 for the design of system functionality.
Figure 2: Connectivity
Remote Display Service App
AKA 245: LON units
only and max 250
controller parameters
System Manager
Display Bus
Modbus
Modbus LON/ TCP/IP (SNMP)
Modbus LON/ TCP/IP (SNMP)
Bluetooth
AK-UI55 Bluetooth
AK-UI55 Set
AK-UI55 Info
Smart Device
(iOS or Android)
AK-CC55 Connect
AK-CC55 Single Coil UI
AK-CC55 Multi Coil
AK-CC55 Compact
KoolProg
Case Controller
Danfoss 80G8333
Data communication
The AK-CC55 Compact controller has built-in MODBUS data communication only.
AK-CC55 Compact
Compact version for controlling one evaporator.
An application mode setting will congure inputs and outputs for the desired use. There are nine applications to
choose from.
Regulation is performed using a TXV in combination with a liquid line solenoid valve, controlling a compressor or an
AKV expansion valve.
AK-CC55 Compact is without display, and can be extended with one external display (see Figure 3 and Figure 4):
External display
There are three versions available with dierent functions:
• AK-UI55 Info: Temperature display.
• AK-UI55 Set: Temperature display with control buttons on the front.
• AK-UI55 Bluetooth: Temperature display with Bluetooth communication, for use with AK-CC55 Connect Mobile
app.
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AK-CC55 Compact

Figure 5: AK-UI55 Info Figure 6: AK-UI55 Set Figure 7: AK-UI55 Bluetooth
AK-CC55 Compact
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Controller functionality
Functions
• Day/night thermostat with ON/OFF or modulating principle
• Switch between thermostat settings via digital input
• Adaptive superheat control
• Adaptive liquid control
• Modulating PWM control of brine valve
• Start of defrost via schedule, digital input, network or setting display
• Natural, electric, simple hot gas, or warm brine defrost.
• Stop of defrost on time and/or temperature
• Coordination of defrosting among several controllers in a line-up
• Pulsing or ECO control of fans when thermostat is satised
• Appliance cleaning function for documentation of HACCP procedure
• Rail heat control via day/night load or dew point
• Door function
• Control of two compressors
• Control of night blinds
• Light control
• Heat thermostat
• High accuracy inputs:
◦to guarantee a better measuring accuracy than stated in the standard EN ISO 23953-2 without subsequent
calibration (Pt1000 ohm sensor).
• Support of user dened temp. sensor type
• Integrated MODBUS communication
Injection control
Adaptive superheat control
Liquid injection in the evaporator is controlled by an electronic injection valve of the type AKV. The valve operates
as both expansion valve and solenoid valve. The controller opens and closes the valve based on sensor readings.
Figure 8: Adaptive superheat control with AKV valve
Danfoss 84B2732
S2
AKV
pe
The superheat is measured via a pressure sensor Pe and temperature sensor S2. By using a pressure sensor, and
temperature sensor a correct measurement of superheat is achieved under all conditions which ensures a very
robust and precise control. The signal from one pressure transmitter can be shared by max. 10 controllers, but only if
there is no signicant pressure dierence between the evaporators in question.
The function contains an adaptive algorithm which independently adjusts the valve’s opening so that the
evaporator constantly supplies optimum amount of refrigerant.
Adaptive liquid control
Adaptive liquid control is used in trans-critical CO2ejector systems, which allow liquid ow. When adaptive liquid
control is initiated, the superheat of the evaporator will be minimized so that a controlled amount of liquid is
present at the outlet of the evaporator.
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AK-CC55 Compact

This type of control requires that the controller receives an on/o signal from (for example) a suction accumulator in
the suction line.
Figure 9: Adaptive liquid control with AKV valve
A level switch in the tank will register when the liquid level exceeds the max. level. When this happens, the
controller will switch to dry expansion, and then back to liquid control when the liquid level has dropped. The
function is dened in setting o02, o37 or o84.
The function can also be activated via data communication from a system unit. If the adaptive liquid control signal is
lost, the controller will automatically switch back to dry expansion.
WARNING:
Accidental actuation may allow liquid throughput to the compressor. It is the installer’s responsibility to ensure that
signal loss to the controller will not result in liquid throughput to the compressor. Danfoss accepts no responsibility
for damage resulting from inadequate installation.
Thermostatic expansion valve control
In the compact version the refrigeration (injection) can be controlled either by starting/stopping a compressor or by
opening/closing a solenoid valve in the liquid line.
Figure 10: AK-CC55 Compact with evaporator, solenoid
valve, expansion valve and sensor positions
S4
S5
S3
Danfoss 84B3267
Brine control
When changing from ON/OFF control to modulating control in TXV applications, a solenoid valve can be PWM
controlled with a set period time from 30 – 900 sec. A number of additional brine control parameters are available in
the injection control menu. When brine control is enabled, a dedicated brine defrost can also be set up in order to
force open the brine valve while defrosting.
AK-CC55 Compact
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1.
2.
Temperature control
The temperature in the appliance is registered by one or two temperature sensors which are located in the return air
before the evaporator (S3) or after the evaporator (S4) respectively. A setting for the thermostat, night thermostat,
alarm thermostat and display reading determines how much the two sensor values should inuence each individual
function, e.g. 50% of S4 will produce an equal value from both sensors.
The actual temperature control can take place in two ways:
As an ordinary ON/OFF regulation with a dierential, or
As a modulating control where the temperature variation will not be nearly as high as in ON/OFF control.
There is, however, a limit to the use of a modulating control as it can only be used in remote cabinets. It is not
recommended to use modulating thermostat control in low temperature applications. In applications with one
evaporator and one compressor, the thermostat function with ON/OFF control should be selected. In remote
cabinets, the thermostat function may either be selected for ON/OFF control or modulating control.
Table 3: Control methods
ON/OFF control
Modulating control
Temperature monitoring
Just as is possible for the thermostat, the alarm monitoring can be set with a weighting between S3 and S4 so that
you can decide how much the two sensor values should inuence the alarm monitoring. Minimum and maximum
limits can be set for alarm temperature and time delays. A longer time delay can be set for high temperature alarm.
This time delay is active for pull-down, after defrosting, appliance cleaning and start-up.
Thermostat bands
Thermostat bands can be used benecially for appliances where dierent product types are stored, which requires
dierent temperature conditions. It is possible to change between the two dierent thermostat bands via a contact
signal on a digital input. Separate thermostat and alarm limits can be set for each thermostat band.
For the defrost control, separate defrost stop temperature and max. defrost time can be set for each thermostat
band. For the compressor control it is possible to disable the second compressor in thermostat band 2 if required.
Figure 11: Thermostat band function with two dierent band settings
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AK-CC55 Compact

1.
2.
3.
Night setback of thermostat value
In refrigeration appliances there may be big load dierences between the shop’s opening and closing hours,
especially if night lids/blinds are used. The thermostat reference may be raised here without it having any eect on
the product temperature.
Change-over between day and night operation can take place as follows:
• via an external switch connected to a digital input
• via a signal from the data communication system
Figure 12: Thermostat band function with Night setback
Temperature sensor types
The S2 and S6 sensors always have to be Pt1000 sensors due to the high measuring accuracy.
For the S3, S4 and S5 sensors, the user can select between the following sensor types:
0 = Pt1000 (Danfoss AKS 11)
1 = PTC1000 (Danfoss EKS 111)
2 = NTC 5k (Danfoss EKS 211)
3 = NTC 10k (Danfoss EKS 221)
4 = User-dened
If “User-dened” is selected, three sensor measuring points must be provided and based on these three sensor
points, a sensor characteristic is generated.
A sensor point is dened by setting a temperature value and the corresponding resistance value at this temperature.
The resistance value is set via two values for kohm and ohm respectively. These values can be found in the data
sheet for the sensor.
The three sensor points must be:
Lowest temperature in wanted measuring range
Highest temperature value in wanted temperature range
Temp. value in the middle where a high measuring accuracy is required
A sensor error is detected at temperature values below/above the min./max. temperature values typed in for the
sensor points.
AK-CC55 Compact
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y
x
A
350
300
250
200
150
100
50
0
-40 -20 0 20 40 60 80
Danfoss 80G8338
x
y
A
Temp [°C]
R [kohm]
Sensor point (-30 °C, 180 kΩ)
1.
2.
3.
Figure 13: Example of sensor points from a NTC sensor
Limitations:
A user dened temperature sensor can only be be dened within the temperature range from -40 – +60 °C and
within the resistance range from 400 – 179.999 ohm.
When applying a new user dened sensor type, please contact Danfoss for validation of compliance and measuring
accuracy.
Appliance cleaning
This function makes it easy for the shop’s sta to carry out a cleaning of the appliance according to a standard
procedure. Appliance cleaning is activated via a pulse signal – as a rule via a key switch placed on the appliance or
via the AK-CC55 Connect mobile app.
Appliance cleaning is carried out via three phases:
At the rst activation, the refrigeration is stopped, but the fans keep on operating in order to defrost the
evaporators. ”Fan” is shown on the display.
At the second activation, the fans are also stopped and the appliance can now be cleaned. ”OFF” is shown on the
display.
At the third activation, refrigeration is recommenced. The display will show the actual appliance temperature,
o97 setting.
When appliance cleaning is activated, a cleaning alarm is transmitted to the normal alarm recipient. A later
processing of these alarms will document that the appliance has been cleaned as often as planned.
There are no temperature alarms during appliance cleaning.
Table 4: Appliance cleaning function
-
+
+
°C
1
÷
+
Fan
2
÷
÷
O
3
+
+
°C
Appliance shutdown
The function closes the AKV valve and all outputs are switched o. The cooling appliance is stopped like the “Main
switch”, but this happens without an “A45 standby alarm”. The function can be enabled by a switch on the DI input
or via a setting through data communication.
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AK-CC55 Compact

Defrost
Depending on the application, you may choose between the following defrost methods:
• Natural: Here the fans are kept operating during the defrost
• Electric: The heating element is activated
• Hot gas: Simple hot gas defrost can be selected in application modes where a compressor is controlled. The
compressor unit will operate during defrosting
• Brine defrost: The brine valve is forced open while defrosting (only possible when selecting modulating control in
TXV applications)
Electrical defrosting
At electrical defrost, an electrical heater is placed in front of the evaporator and the fan will “pull” the hot air through
the evaporator during defrosting.
Figure 14: Electrical defrosting
Danfoss 84B8330
S3
S4
S5
M M
Simple hot gas defrosting
If hot gas defrost is selected in application 1-5, the compressor will be running during defrost and a hot gas valve
(HGV) is bypassing the compressor discharge gas to the evaporator inlet and thereby the evaporator is defrosted.
Natural defrost
At natural defrost, the ice is melted by running the fans and thereby circulating warm air through the evaporator.
Figure 15: Natural defrost
Danfoss 84B8331
S3
S4
S5
M M
Start of defrost
A defrost can be started in dierent ways:
Interval:
Defrost is started at xed time intervals like e.g. every eighth hour. An interval must ALWAYS be set to a "higher"
value than the period set between two defrostings when a schedule or network signal is used.
Week schedule:
Here defrost can be started at xed times of the day and night. However, max. 6 defrosts per day.
Contact:
Defrost is started with a contact signal on a digital input.
AK-CC55 Compact
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1.
2.
3.
4.
5.
6.
Figure 16: Defrost start
Network:
The defrost start signal is received from a system manager via data communication.
Max. thermostat runtime:
When the aggregate time has passed a preset value, a defrost will be initiated.
Manual:
An extra defrost can be activated from the defrost button on the AK-UI55 Set display via the app, or via the
parameter setting. All the mentioned methods can be used in parallel – if just one of them is activated, a defrost will
be started.
Stop of defrost
Defrosting can be stopped by either:
• Time
• S4A temperature (with time as safety)
• S5A temperature (with time as safety)
When the selected defrost stop sensor reaches the set defrost stop limit, the defrost is terminated. If the defrost stop
sensor does not reach the set defrost stop limit within the set max. defrost time, the defrost will be terminated on
time.
Minimum defrost time
When using hot gas for defrosting, the heat is coming from within the evaporator, and this means that the S5 sensor
is rising fast when the inner layer of ice is melted. This will sometimes cause parts of the evaporator not to be
defrosted when defrost is terminated on S5 evaporator temperature.
To prevent this, the user is given the option of setting a minimum defrost time. When a defrost is initiated, it will
have to run for the set minimum time even if the set defrost stop limit has been reached by the selected defrost stop
sensor.
Defrost sequence
When a defrost is initiated, the controller will run through the following sequence:
Pump down: where the evaporator is emptied of refrigerant
Defrost: where the ice on the evaporator is melted
Hold after defrosting: where multiple controllers wait for each other (coordinated defrost)
Drip o: where remaining water is dripping o evaporator
Drain delay (Hot gas only): where the drain valve is opened to drain the liquid refrigerant
Fan delay: where the fans are restarted when the remaining water on the evaporator has turned into ice
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AK-CC55 Compact

BA C D E
Danfoss 84B8332
X
AKV
x
A
B
C
D
E
Time
Pump down
Defrost
Hold
Drip
Fan delay
1.
2.
3.
4.
Figure 17: Electrical defrost sequence
During an electrical defrost sequence where the defrost heater is ON during defrost, AKV valve is closed and fans are
running during defrost but stopped during drip.
Fan control during defrost
During the defrost sequence, the evaporator fans can be controlled in one of the following ways:
The fan is OFF in the entire defrost sequence
The fan is ON during the entire defrost sequence except during fan delay state
The fan is ON during defrost state and is OFF in the rest of the defrost sequence
Like option 2, however the fans can be stopped if the selected defrost stop sensor exceeds a set fan stop limit
Real-time clock
The controller has a built-in real-time clock which can be used to start defrosts. This clock has a power reserve of
four days.
If the controller is equipped with data communication, the clock will automatically be updated from a Danfoss
system manager.
Coordinated defrost
There are two ways in which coordinated defrost can be arranged.
Figure 18: Coordinated defrost options
System manager
Max 10.
Danfoss 84B8268
Either with wire connections between the controllers or via data communication:
Wire connections
The digital input DI2 must be congured for coordinated defrost and wiring must be connected between the
relevant controllers. When one controller starts a defrost, all the other controllers will follow suit and likewise start a
defrost. After the defrost, the individual controllers will move into waiting position. When all are in waiting position
there will be a change-over to refrigeration.
AK-CC55 Compact
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Coordination via data communication
Here the system manager handles the coordination. The controllers are gathered in defrosting groups and the
system manager ensures that defrosting is started in the group according to a weekly schedule.
When a controller has completed defrosting, it sends a message to the system manager and then goes into a
waiting position. When every controller in the group is in a waiting position, refrigeration is again permitted in all
the individual controllers.
Melt function
This function will prevent the air ow in the evaporator from being reduced by frost created by uninterrupted
operation for a long time.
The function is activated if the thermostat temperature has remained in the range between -5 °C and +10 °C for a
longer period than the set melting interval. The refrigeration will then be stopped during the set melting period.
The frost will be melted so that the air ow and hence the evaporator’s capacity will be greatly improved.
Control of two compressors (only with custom set-up)
Two compressor steps can be controlled cyclic or sequentially. At cyclic control, two compressors must be of the
same size, while in sequential control compressor step 1 can be larger than step 2.
Figure 19: Control of two compressors.
Cyclic control
When the controller demands refrigeration, it will rst cut in the compressor with the shortest operating time. After
the time delay, the second compressor will be cut in.
When the temperature has dropped to ”the middle of the dierential”, the compressor with the longest operation
time will be cut out.
The running compressor will continue until the temperature has reached the cut-out value. Then it will cut out.
When the temperature again reaches the middle of the dierential, a compressor will again be started.
If one compressor cannot maintain the temperature within the dierential, the second compressor will also be
started.
If one of the compressors has run on its own for two hours, the compressors will be changed over so that
operational time is balanced.
The two compressors must be of a type that can start up against a high pressure.
The compressor's settings for ”Min. On time” and ”Min. O time” will always have top priority during normal
regulation. But if one of the override functions is activated, like e.g. defrost, door open function, case shutdown,
forced closing, the ”Min. On time” will be disregarded.
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AK-CC55 Compact

Sequential control
Compressor steps are controlled in the same manner as described for cyclic control, but compressor step 1 will
always be started rst and cut out as the last one. No time equalization is available in sequential control mode.
Thermostat band
In thermostat band 2, it is possible to disable the operation of the second compressor.
Rail heat
It is possible to pulse-control the power to the rail heat in order to save energy. Pulse control can either be
controlled according to day/night load or dewpoint.
Relay or analogue output
A relay output can be used when long cycle times are permitted. If fast pulsing is required, the AO1/PWM output
can be used. The output must be connected to an external power solid state relay. The cycle time must be
congured for the relay output in o43 or for analogue output in P82.
Pulse control according to day and night
Various ON periods can be set for day and night operation. A cycle time is set as well as the percentage part of the
period in which the rail heat is ON.
Figure 20: Rail heat control, day/night load.
Pulse control according to dewpoint
In order to use this function, a system manager of the type AK-SM is required which can measure ambient
temperature and humidity to calculate dewpoint and distribute to the appliance controllers. For this the rail heat’s
ON period is controlled according to the distributed dewpoint.
Two dewpoint values are set in the appliance control:
• One where the eect must be max. i.e. 100%. (o87)
• One where the eect must be min. (o86)
At a dewpoint which is equal to or lower than the value in 086, the eect will be the value indicated in o88. In the
area between the two dewpoint values, the controller will manage the power to be supplied to the rail heat.
AK-CC55 Compact
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Figure 21: Rail heat control, dewpoint
Danfoss 84B2729
o88
o86
100%
o87
During defrosting
During defrosting rail heat will be active, as selected in setting d27.
Fan
Pulse control
To obtain energy savings, it is possible to pulse control the power supply to the evaporator fans.
Pulse control can be accomplished in one of the following ways:
• during the thermostat’s cut-out period (cold room)
• during night operation and during the thermostat’s cut-out period (appliance with night blinds) (The function is
not actual when r14=2, i.e. modulating regulation).
A period of time is set as well as the percentage of this period of time where the fans have to be operating.
Figure 22: Fan cycle time
Cut-out of fans during plant breakdowns
If the refrigeration in a breakdown situation stops, the temperature in the cold room may rise quickly as a result of
the emission of heat from large fans. In order to prevent this situation, the controller can stop the fans if the
temperature at S5 exceeds a set limit value. The fans will start running again when the S5 temperature has dropped
2K below the set limit. (The function can also be used as a type of MOP function. Here the load on the compressors
is limited until the S5 temperature has fallen below the congured value).
Fan ECO operation (only custom set-up)
Fan ECO operation is used to reduce fan speed during night operation – typically on cabinets with night blinds.
The function is enabled when a relay has been congured for Fan ECO function in one of the applications with
custom set-up of relay functions.
The fan economy control (fan speed) is controlled via the two fan outputs:
• Fan output
• Fan Eco output
If the Fan output is activated, then the fan is running with 100% speed.
If the Fan ECO output is also activated, then the fan is running with reduced speed (typically 50%).
If both fan outputs are de-activated, then the fans are stopped.
© Danfoss | Climate Solutions | 2022.08 BC365212986197en-000201 | 19
AK-CC55 Compact

Y
X
100%
50%
0%
A
B
Danfoss 84B8318
X
Y
A
B
Time
Fan speed
Fan
Fan ECO
1.
2.
3.
4.
5.
Figure 23: Fan ECO control – Fan speed reduced to 50% during night operation
The fans will always run with full speed during day operation, rst stage of case cleaning, defrost, forced cooling and
when air heating is active.
Light function
The function can be used for controlling the light in a refrigeration appliance or in a cold room. It can also be used
for controlling a motorised night blind.
The light function can be dened in several ways:
The light is controlled via the day/night function. A digital input setup for light control can switch light ON, if the
light is switched o during night
The light is controlled by a system manager via the parameter o39. A digital input setup for light control can
switch light ON, if the light is switched o by the system manager.
Light is controlled via the door switch. Light is switched ON when door is opened and switched OFF 2 minutes
after the door has been closed.
Like option 2, but here the light is switched ON automatically if the communication to the system manager has
been lost for 15 minutes
Light is only controlled via a digital input setup for light control
The light load must be connected to the NC terminals on the relay.
This ensures that the light remains ON in the appliance if power to the controller should fail.
A setting denes how light is controlled when regulation is stopped via r12 Main switch = OFF (see o98). The light is
switched o when the appliance cleaning function is activated.
Night blind
Motorised night blinds can be controlled automatically from the controller. The night blinds will follow the status of
the light function. When the light is switched on, the night blinds open, and when the light is switched o, the night
blinds close again. When the night blinds are closed, it is possible to open them using a switch signal on the digital
input. If this pulse signal is activated, the night blinds will open and the refrigeration appliance can be lled with
new products. If the pulse signal is activated again, the blinds close.
When the night blind function is used, the thermostat function can control with dierent weighting between the S3
and S4 sensors. A weighting during day operation and another when the blind is closed.
A night blind is opened when the appliance cleaning function is activated.
A setting can dene that the night blind is opened when "r12" (Main switch) is set to o (see o98).
When the night blind rolls down, the fan will be stopped for the set time. The night blind can thereby roll down to
the correct position.
AK-CC55 Compact
© Danfoss | Climate Solutions | 2022.08 BC365212986197en-000201 | 20