Failsafe Functions; Injection Function; Thermostat Function; Defrost Function - Danfoss ADAP-KOOL AKC 114 G Mode D'emploi

Fail safe functions
AKC 114G

Injection function

Sensor error
Error on sensors attached to injection function S2( ) or AKS 32R. The sensor is
interrupted, shortcircuited or not mounted.
The controller gives an alarm. There is change-over to emergency operation. During
the emergency operation the valve's degree of opening is 50% of the opening degree
registered as valid for the load, when the error occurred. In this state the thermostat
function is NOT active, i.e. there is continuous cooling.
No signal from AKS 32, lack of liquid/liquid flow through evaporator
If an "unexpected" signal is registered from the pressure transmitter, the valve will be
controlled by force. If it is not possible to create a sufficient superheat, there will be an
alarm.
Typically the alarm will be caused by:
- Ice on the evaporator (inadequate defrost)
- Evaporator fans stopped (breakdowns etc.)
- Unintentional compressor stop

Thermostat function

Sensor error:
Error on sensors attached to the thermostat function S3( ) or S4( ). The sensor is either
interrupted, shortcircuited or not mounted.
If no signal is received from the thermostat sensor, there will be a change-over to
emergency operation where the expansion valve will be controlled by force at 50% of
the opening degree registered as valid for the load, when the error occurred.
NB! If there are errors on both thermostat sensor and S2 sensor for a given function, the
AKV valve will close until the error has been made good.

Defrost function

(hotgas regulation only)
Sensor error
Error on sensor attached to the defrost function "DefStop Sx".
The sensor is either interrupted, shortcircuited or not mounted.
The controller gives an alarm and sends a message.
When there is an error in an Sx sensor, the defrost will be based on time.

Delayed fan start

(hotgas regulation only)
Sensor error
The S5 sensor is either interrupted, shortcircuited or not mounted. The controller gives
an alarm and sends a message.
The fans will start immediately after a possible injection time delay.

Fan stop

(hotgas regulation only)
If there is a defect in the refrigerating plant where cooling is stopped unintentionally (e.g.
compressor stop or lack of liquid), the fans can be stopped. In this way there will be no
unnecessary supply of power to the room before the defect is repaired. The application will
typically be large rooms with large fans.
The fans will stop when the S5 temperature exceeds the set temperature value "FanStop °C".
When the temperature has again dropped below this value, the fans will start.
When the S5 sensor is defective, the function is inactive.
In connection with defrost, start-up after defrost and forced closing signal, the function is
overridden (the FanStop °C value is ignored).
The function only applies to the setting "Ther.Mode" is in position 1.
Common Controller Safety Function Fan Stop by S5
Function description RC.8A.R1.02 © Danfoss 10/2001
OFF / ON
FanStopS5
FanStop ° C ___
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