Specifications

102 RK0YG302 © Danfoss 05/2007
Modulating control
EKC 414C1
EKC 414C1
Liquid supply
The supply of liquid is controlled on the basis of signals from
three sensors (S1, S2 and an air sensor which may be placed
before or after the evaporator). The sensors register the dierence
between the temperature at the evaporator outlet (S2) and the
temperature at the evaporator inlet (S1). In conjunction with the
air temperature the sensors create a signal, so that superheat
is continuously kept at a minimum, whatever the operating
conditions.
The placing of the S1 sensor is of crucial importance for a reliable
signal, and hence for a satisfactory operation.
The AKV valve functions both as expansion valve and solenoid
valve. The valve opens and closes based on signals from the
controller.
The controller can be used in refrigeration appliances where the
evaporator consists of two spirals. The S3 sensor is here used as
defrost sensor for spiral 2/section 2.
Temperature control
The temperature is controlled on the basis of signals from one
or two temperature sensors. If there is only one sensor it may
optionally be placed in the air before or after the evaporator. If
there are two sensors, one must be placed before and one after
the evaporator. With a setting it is subsequently dened how
large an inuence the individual sensor is to have on the control.
The actual temperature control can take place in two ways: as
an ordinary ON/OFF regulation with a belonging dierential, or
as a modulating control there the temperature variation will not
be nearly as great as in ON/OFF control. There is however a limit
to the use of them as a modulating control can only be used in
central plant. In a decentralised plant the thermostat function
with ON/OFF control should be selected.
In a central plant the thermostat function may either be selected
for ON/OFF control or modulating control.
Defrost
With a simple function defrost can be started x times per day and
night. But the controller may also receive a signal from a defrost
clock or from another unit via the data communication, so that
defrost will take place at dened times of the day or night.
An on-going defrost can be stopped based on temperature,
normally the one measured with the S5 sensor, or it may be
stopped based on time. A combination with stop based on
temperature and with the time factor as a precautionary measure
is also a possibility.
On/O control