User manual

Rittal enclosure cooling unit 7
3 Product description
EN
3.1.2 Components
Fig. 2: Main components of cooling unit
Key
1Cover
2 Chassis
3 Connection box
4Evaporator fan
5Handle
6 Air outlet opening
7 Lower louvred grille for air inlet
8Display
9 Infill panel
10 Upper louvred grille for air outlet
11 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
– In the refrigerant circuit, the cooling units have a type-
tested pressure monitor (to EN 12263) which switches
off the cooling unit if the maximum admissible pres-
sure is exceeded. Once the pressure drops back be-
low 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 floating contacts on the connection
pins on terminals 1 and 3 of the signal connector (X2),
via which system messages from the device may be
polled, e.g. using a PLC (2 x normally closed or nor-
mally open contacts).
3.1.5 Condensation
At high levels of humidity and low temperatures inside
the enclosure, condensate water may form on the evap-
orator coil.
The cooling units have an automatic electrical conden-
sate water evaporator. The thermal component used for
this purpose is based on self-regulating PTC technolo-
gy. Condensate water 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 com-
ponent and is evaporated (through-flow heater princi-
ple). The water vapour streams out of the cooling unit
with the airflow from the external fan.
The PTC thermal component is activated automatically
when the compressor is running, and continues to run
for around 15 minutes after the compressor has been
switched off. During the after-run phase, the condenser
fan will likewise continue to run at low speed.
In the event of a short-circuit in the PTC component or if
there is a risk of inverter overload (possible at high ambi-
ent temperatures), the PTC component will be deacti-
vated. This means that any condensate water arising
can be discharged via the safety overflow.
If the fuse has tripped, any condensate water is drained
off via the safety overflow. The condensation is routed
downwards out of the unit via a drain pipe on the evap-
orator coil divider panel. For this purpose, a hose may be
connected to the condensate water nozzle (see section
5.3.8 "Connect the condensate water discharge").
3.1.6 Filter mats
The entire cooling unit condenser is covered with a dirt-
repelling, easy-to-clean RiNano coating. In many appli-
cations, therefore, the use of filter media is unnecessary,
particularly with dry dusts.
For dry, coarse dust and lint in the ambient air, we rec-
ommend installing an additional PU foam filter mat (avail-
able as an accessory) in the cooling unit. Depending on
the incidence of dust, you will need to replace the filter
mat from time to time (see section 8 "Inspection and
maintenance").
For oily ambient air, we recommend the use of metal fil-
ters (also available as an accessory). These may be
cleaned with suitable detergents and reused.