Rittal SK 3302.100 Assembly And Operating Instructions Manual - 6 Operation
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Rittal cooling unit assembly and operating instructions
6 Operation
EN
– Protective function to prevent icing
– Monitoring of all motors (compressor,
condenser fan, evaporator fan)
– Phase monitoring for three-phase units
– Master-slave function with a maximum of ten units.
One device functions as a master unit. Once the
set temperature is reached by one of the connect-
ed slave devices or in the event of the door limit
switch function, the affected slave unit will report
to the master unit, which will switch all the other
cooling units on or off as required.
– Switching hysteresis: Adjustable within the range
2 – 10 K, preset to 5 K.
– Visualisation of the current enclosure internal tem-
perature and all error messages in the 7-segment
display.
– Using an interface card (Model No. SK 3124.100),
the unit may be incorporated into higher-level
remote monitoring systems such as the Rittal
Computer Multi Control CMC.
The cooling unit operates automatically i.e. after
switching on the power supply, the evaporator fan
(see Fig. 2, page 5) starts to run and circulates the
internal enclosure air. The compressor and con-
denser fan are regulated by the e-Comfort controller.
The e-Comfort controller has a 7-segment display
(Fig. 34, no. 4). After switching on the power supply,
the current software version initially appears on this
display for approx. 2 seconds, as well as the activat-
ed eco-mode. Followed by a preset option (e. g. t10)
or the temperature.
In regular operation, the display shows both the tem-
perature (in degrees Celsius or Fahrenheit – users
may switch between the two) and any error messages.
The current enclosure internal temperature is usually
displayed permanently. In the event of an error mes-
sage, this will alternate with the temperature display.
The unit is programmed using buttons 1 – 3 (Fig. 34).
The relevant parameters also appear in the display.
6.2.2 Eco-mode
All Rittal TopTherm cooling units with e-Comfort
controller from firmware 3.2 have the energy-saving
eco-mode, which is activated in the delivered state.
The eco-mode is used to save energy in the cooling
unit if there is no thermal load, or there is a low ther-
mal load in the enclosure (e. g. standby operation,
no production or weekend). During this process the
evaporator fan in the internal circuit is switched off as
appropriate if the actual enclosure internal tempera-
ture drops to 10 K below the setpoint temperature
set. To reliably measure the internal temperature
also during this process, the fan starts cyclically for
30 sec. (see Fig. 35). If the internal temperature
reaches the range 5 K below the setpoint set again,
the fan switches back to continuous operation.
If required, the eco-mode can be deactivated via the
control display. For this purpose switch the parame-
ter from 1 to 0 in the programming level (see Tab. 4,
page 25). The fan then runs continuously.
Fig. 35:
Diagram of eco-mode
6.2.3 Launching test mode
The e-Comfort controller is equipped with a test func-
tion whereby the cooling unit commences cooling
operation independently of the set temperature or
door limit switch function.
• Simultaneously press buttons 1 and 2 (Fig. 34)
for at least 5 sec.
The cooling unit will commence operation.
After approximately 5 minutes, test mode will end.
The unit switches off and changes to normal oper-
ation.
6.2.4 General programming information
Using buttons 1, 2 and 3 (Fig. 34) you can change
24 parameters within the preset ranges (min. value –
max. value).
Tables 4 and 5 show the parameters which can be
altered. Fig. 36 of page 26 shows which buttons
must be pressed.
Note on switching hysteresis:
With a low hysteresis and short switching
cycles, there is a risk that cooling may not
be adequate or that only partial sections
of the enclosure are cooled. If the cooling
unit is oversized and compressor running
times are
is automatically increased to protect the
cooling unit.
Note on temperature settings:
With the e-Comfort controller, the tempe-
rature is preset at the factory to +35°C.
In order to save energy, and due to the
risk of increased condensation, do not set
the temperature lower than that actually
necessary.
Note on useful cooling output:
Interactive performance diagrams for
calculating the useful cooling output may
be found at www.rittal.com.
ON
Internal fan
status
Internal
temperature
Time
Setpoint
–5°C
Setpoint
–10°C
OFF
10 min.
30 sec.
10 min.