Defrost Function - Danfoss AK-CC55 User Manual

User Guide | Controller for appliance control, AK-CC55
Defrost
The controller contains a timer function that is zero-set 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
displaced 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, hot gas 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.
0 = No defrost, 1 = El, 2 = Gas, 3=Brine, 4=air circulation only
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.
Interval between defrost starts
The function is zero-set 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 defrosts 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 communication 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.
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.
(The setting is the defrost time if d10 is set to 0.)
Time staggering for defrost cut-ins 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.
Drip-off time
Here you set the time that is to elapse from a defrost and until the compressor is to
start again. (The time when water drips off the evaporator).
50 | BC308437742037en-000101
Defrost control
d01 Def. method
d02 Def. Stop Temp
d03 Def Interval
(0=off )
d04 Max Def. time
d05 Time Stagg.
d06 DripOff time
© Danfoss | DCS (vt) | 2019.09