Danfoss EKC 202 Manual page 9

Controller for temperature control
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Alarm delay (short alarm delay)
If one of the two limit values is exceeded, a timer function will commence. The alarm will not
become active until the set time delay has been passed. The time delay is set in minutes.
Time delay for door alarm
The time delay is set in minutes.
The function is defined in o02.
Time delay for cooling (long alarm delay)
This time delay is used during start-up, during defrost, immediately after a defrost.
There will be change-over to the normal time delay (A03) when the temperature has dropped
below the set upper alarm limit.
The time delay is set in minutes.
Upper alarm limit
Here you set when the alarm for high temperature is to start. The limit value is set in °C (absolute
value). The limit value will be raised during night operation. The value is the same as the one set
for night setback, but will only be raised if the value is positive.
The limit value will also be raised in connection with reference displacement r39.
Lower alarm limit
Here you set when the alarm for low temperature is to start. The limit value is set in °C (absolute
value).
The limit value will also be raised in connection with reference displacement r39.
Delay of a DI alarm
A cut-out/cut-in input will result in alarm when the time delay is passed. The function is defined
in o02.
High alarm limit for condenser temperature
If the S5 sensor is used for monitoring the condenser's temperature you must set the value at
which the alarm is to become activated. The value is set in °C.
The definition of S5 as condenser sensor is accomplished in o70. The alarm is zeroset again 10 K
below the set temperature.
Compressor
The compressor relay works in conjunction with the thermostat. When the thermostat calls for
refrigeration will 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)
Min. OFF-time (in minutes)
Reversed relay function for compressor relay
0: Normal function where the relay cuts in when refrigeration is demanded
1: Reversed function where the relay cuts out when refrigeration is demanded (this wiring pro-
duces the result that there will be refrigeration if the supply voltage to the controller fails).
Defrost
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 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. If there is a risk of power
failure for periods longer than four hours, a battery module should be mounted in the controller.
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
defrosts do not "come tumbling" one after the other.
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 tempera-
ture sensor.
Defrost method
Here you set whether defrost is to be accomplished with electricity or "non".
During defrost the defrost relay will be cut in.
When gas defrosting the compressor relay will be cut in during defrost.
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.
EKC 202
Manual RS8DZ602 © Danfoss 08-2010
A03
Alarm delay
A04
DoorOpen del
A12
Pulldown del
A13
HighLim Air
A14
LowLim Air
A27
AI.Delay DI
A37
Condtemp Al.
Reset alarm
Compressor control
c01
Min. On time
c02
Min. Off time
c30
Cmp relay NC
Defrost control
d01
Def. method
d02
Def. Stop Temp
9

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