3 Product description
EN
8
Rittal enclosure cooling unit
3.1.2
Components
Fig. 2:
Main components of cooling unit (SK 317880x/
SK 317980x)
Fig. 3:
Main components of cooling unit (SK 31848x0)
1
Louvred grille
1a
Top louvred grille
1b
Bottom louvred grille
2
Service label
3
Air outlet, outside
4
Display including NFC interface
5
Air inlet, outside
6
Cover
7
Electrical connections and interfaces
8
Air inlet, inside
9
Mounting point, potential equalisation
10
Rating plate
11
Rear panel
12
Mounting point, IoT interface
13
Air outlet, inside
14
Foamed-in seal
15
Thread for eyebolt
3.1.3
Control
Rittal enclosure cooling units are fitted with a controller
for setting the functions of the cooling unit.
Operation using this controller is described in section 7
"Operation".
3.1.4
Safety devices
– The cooling units are equipped with various features to
prevent inadmissible pressure increases in the cooling
cycle. If an unusually high pressure nevertheless oc-
curs, the compressor may be temporarily and auto-
matically deactivated via a safety device. Once the
pressure drops back below the admissible pressure,
the unit will automatically resume operation.
– Temperature monitoring prevents the evaporator coil
from icing over. If there is a risk of icing, the compres-
sor switches itself off and automatically switches itself
back on again at higher temperatures.
– The compressor is monitored and protected by the in-
verter to prevent overloading.
– The fans have a built-in overload protection with auto-
matic reset.
– 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-energising),
the device will switch back on with a delay of 180 sec-
onds.
– The device has a floating contact on the connection
pins on terminals 2 and 3 of the signal connector (X3),
via which system messages from the device may be
polled, e.g. using a PLC.
3.1.5
Condensation
At high levels of humidity and low temperatures inside
the enclosure, condensate water may form on the evap-
orator coil.
All cooling units except SK 3178801 and SK 3179801
have automatic electric condensate evaporation. The
thermal component used for this purpose is based on
self-regulating PTC technology. Condensate water aris-
ing on the evaporator coil is collected in a tank in the ex-
ternal circuit of the cooling unit, and partially evaporated
via the airflow. When the water level rises, the water en-
ters the PTC thermal component and is evaporated
(through-flow heater principle). The water vapour
streams out of the cooling unit with the airflow from the
external fan.
If there is a short-circuit in the PTC element, the separate
PTC fuse will trip and the condensate can be drained off
via the safety overflow.
The condensate is routed out of the unit via the evapo-
rator tray overflow. For this purpose, a hose may be con-
nected to the condensate nozzle (see section 5.3.6
"Connect the condensate water discharge").
6
7
8
5
4
3
2
1
9
10
11
12
13
14
6
7
15
8
5
4
3
2
1a
1b
9
10
11
12
13
14
