Rittal enclosure cooling unit 11
3 Device description
EN
sor switches itself off and automatically switches itself
back on again at higher temperatures.
– The refrigerant compressor and the fans are equipped
with thermal winding shields to protect against excess
current and excess temperatures.
– In order to allow a reduction of pressure inside the
compressor and hence a safe restart, once it has been
switched off (e.g. upon reaching the set temperature
via the door limit switch function or via de-energizing),
the device will switch back on with a delay of 180 sec-
onds.
– The device has floating contacts on the connection
pins (terminals 3 – 5), via which system messages
from the device may be polled, e.g. using a PLC (2 x
normally open contacts e-Comfort controller).
3.1.5 Condensation
At high levels of humidity and low temperatures inside
the enclosure, condensation may form on the evapora-
tor coil.
The cooling units (except 3303.xxx) have automatic,
electric condensate evaporation. The thermal compo-
nent used for this purpose is based on self-regulating
PTC technology. Condensate arising on the evaporator
coil is collected in a tank in the external circuit of the
cooling unit, and partially evaporated via the airflow.
When the water level rises, the water enters the PTC
thermal component and is evaporated (through-flow
heater principle). The water vapor streams out of the
cooling unit with the airflow from the external fan. The
PTC thermal component is permanently connected and
has no switch point. It is protected against shortcircuits
with miniature fuses (F1.1, F1.2). If the fuse has tripped,
any condensation is drained off via the safety overflow.
3.1.6 Filter mats
The cooling unit condenser is finished all over with a dirt-
repelling, easy-to-clean RiNano coating. These UL list-
ed, type NEMA 12/3R/4 models only accept Rittal's
metal filters. See section7.2 "Cleaning the filter mat" for
additional information regarding filters. These filters may
be cleaned with suitable detergents and reused.
3.1.7 Door limit switch
The cooling unit may be operated with a floating door
limit switch connected. The door limit switch is not in-
cluded with the supply (available as an accessory, Model
No. PS 4127.010).
The door limit switch function causes the fans and the
compressor in the cooling unit to be switched off after
approximately 15 seconds when the enclosure door is
opened (contacts 1 and 2 closed). This prevents the for-
mation of condensation inside the enclosure while the
enclosure door is open. In order to prevent damage to
the unit, it is equipped with an ON delay: The evaporator
fan cuts back in with a delay of approximately 15 sec-
onds after the door has been closed, while the condens-
er fan and compressor switch on after approximately 3
minutes.
3.1.8 Additional interface X3
For incorporating the cooling unit into superordinate
monitoring systems, the IoT interface, together with the
Blue e IoT adaptor, can be connected to the 9-pole
SUB-D connector (available as accessories: IoT inter-
face Model No. 3124.300, Blue e IoT adaptor Model No.
3124.310).
3.2 Proper use, foreseeable misuse
The cooling unit is intended exclusively for cooling
closed control cabinets as well as for professional use in
accordance with DIN EN 61000-3-2. Any other use is
not permitted.
– The unit must not be installed and operated in loca-
tions which are accessible to the general public (see
DIN EN 60335-2-40, paragraph 3.119).
– The unit is designed solely for stationary use.
The cooling unit is state of the art and built according to
recognised safety regulations. Nevertheless, improper
use can pose a threat to the life and limb of the user or
third parties, or result in possible damage to the system
and other property.
Consequently, the cooling unit must only be used prop-
erly and in a technically sound condition! Any malfunc-
tions which impair safety should be rectified immediate-
ly.
Proper use also includes the observance of the docu-
mentation provided, and compliance with the inspection
and maintenance conditions.
Rittal GmbH & Co. KG is not liable for any damage which
may result from failure to comply with the documenta-
tion provided. The same applies to failure to comply with
the valid documentation for any accessories used.
Inappropriate use may be dangerous. Examples of inap-
propriate include:
– Use of the cooling unit over long periods with the en-
closure open.
– Use of the cooling unit when it is standing on the
ground.
– Use of impermissible tools.
– Improper operation.
– Improper rectification of malfunctions.
Note:
No external voltage must be applied to the
door contacts (terminals 1 and 2).
Note:
The electrical signals at the interface are of an
extra-low voltage (not extra-low safety volt-
ages to EN 60 335).