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AK-CC 550
Manual RS8EN502 © Danfoss 02-2010
17
Compressor
Compressor control
The compressor relay works in conjunction with the thermostat. When the thermo
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stat calls for refrigeration the compressor relay be operated.
Running times
To prevent irregular operation, values can be set for the time the compressor is to run
once it has been started. And for how long it at least has to be stopped.
The running times are not observed when defrosts start.
Min. ON-time (in minutes)
c01
Min. On time
Min. OFF-time (in minutes)
c02
Min. Off time
Time delay for couplings of two compressors
Settings indicate the time that has to elapse from the first relay cuts in and until the
next relay has to cut in.
c05
Step delay
The LED on the controller’s front will show whether refrigeration is in progress.
Comp Relay
Here you can read the status of the
compressor relay.
Defrost
Defrost control
The controller contains a timer function that is zeroset after each defrost start.
The timer function will start a defrost if/when the interval time is passed.
The timer function starts when voltage is connected to the controller, but it is dis
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placed the first time by the setting in d05.
If there is power failure the timer value will be saved and continue from here when
the power returns.
This timer function can be used as a simple way of starting defrosts, but it will always
act as safety defrost if one of the subsequent defrost starts is not received.
The controller also contains a real-time clock. By means of settings of this clock and
times for the required defrost times, defrost can be started at fixed times of the day.
Defrost start can also be accomplished via data communication, via contact signals or
manual start-up.
All starting methods will function in the controller. The different functions have to be
set, so that multiple defrosts are avoided..
Defrost can be accomplished with electricity, hotgas or brine.
The actual defrost will be stopped based on time or temperature with a signal from a
temperature sensor.
Defrost method
Here you set whether defrost is to be accomplished with electricity, gas, or (none).
During defrost the defrost relay will be cut in.
d01
Def. method
0 = non
1 = El
2 = Gas
Defrost stop temperature
The defrost is stopped at a given temperature which is measured with a sensor (the
sensor is defined in d10).
The temperature value is set.
d02
Def. Stop Temp
Interval between defrost starts
The function is zeroset and will start the timer function at each defrost start. When
the time has expired the function will start a defrost.
The function is used as a simple defrost start, or it may be used as a safeguard if the
normal signal fails to appear.
If master/slave defrost without clock function or without data communication is used,
the interval time will be used as max. time between defrosts.
If a defrost start via data communcation does not take place, the interval time will be
used as max. time between defrosts.
When there is defrost with clock function or data communication, the interval time
must be set for a somewhat longer period of time than the planned one, as the
interval time will otherwise start a defrost which a little later will be followed by the
planned one.
In connection with power failure the interval time will be maintained, and when the
power returns the interval time will continue from the maintained value.
The interval time is not active when set to 0.
d03
Def Interval
(0=off)
Max. defrost duration
This setting is a safety time so that the defrost will be stopped if there has not already
been a stop based on temperature or via coordinated defrost.
d04
Max Def. time
Time staggering for defrost cutins during start-up
The function is only relevant if you have several refrigeration appliances or groups
where you want the defrost to be staggered in relation to one another. The function is
furthermore only relevant if you have chosen defrost with interval start (d03).
The function delays the interval time d03 by the set number of minutes, but it only
does it once, and this at the very first defrost taking place when voltage is connected
to the controller.
The function will be active after each and every power failure.
d05
Time Stagg.