Operation - Danfoss EKC 202D Manual

Operation

Sensors
Up to two thermostat sensors can be connected to the controller.
The relevant application determines how.
A sensor in the air before the evaporator:
This connection is primarily used when control is based on area.
A sensor in the air after the evaporator:
This connection is primarily used when refrigeration is controlled
and there is a risk of a too low temperature near the products.
A sensor before and after the evaporator:
This connection offers you the possibility of adapting the
thermostat, the alarm thermostat and the display to the relevant
application. The signal to the thermostat, the alarm thermostat
and the display is set as a weighted value between the two
temperatures, and 50% will for example give the same value from
both sensors.
The signal to the thermostat, the alarm thermostat and the display
can be set independently of one another.
Defrost sensor
The best signal concerning the evaporator's temperature
is obtained from a defrost sensor mounted directly on the
evaporator. Here the signal may be used by the defrost function,
so that the shortest and most energy-saving defrost can take
place.
If a defrost sensor is not required, defrost can be stopped based
on time, or S4 can be selected.
Change of temperature reference
In an impulse appliance, for example, used for various product
groups. Here the temperature reference is changed easily with
a contact signal on a digital input. The signal raises the normal
thermostat value by a predefined amount. At the same time the
alarm limits with the same value are displaced accordingly.
EKC 202D Manual RS8EE202 © Danfoss 08-2010 3