5 Commencing operation and control behavior
page
4
of
13
Rittal cooling unit assembly and operating instructions
5.1.2
Editable parameters
Param.
Type
Display
screen
Parameter
Min.
value
Max.
value
Factory
setting
Description
F
PS
Password
0
99
22
Protection code for modifying the configu-
ration parameters (default=22). The value
of the password can be customized from
the supervisor
S
St
Setpoint
r1
r2
35
:r1 minimum value and r2 maximum
value of the set point. Parameter St de-
termines the desired temperature to be
maintained inside the cabinet or cold
room (set point).
F
rd
Regulation diffe-
rential
0
+19
5
Value that is added to (or subtracted
from, i
n „reverse‟ mode) the temperature
set point.
rd= low values:
more precise temperature control;
high compressor On/Off switching
frequency in the event of minimum.
Temperature deviations (with the risk
of causing damage).
rd= high values:
less precise temperature control;
low compressor On/Off switching
frequency in the event of minimum
temperature deviations.
Important:
the compressor can also be
safeguarded using the parameters that
limit the number of activations/hour and
the minimum off time
C
r1
Setpoint min.
value
20
r2
30
r1 & r2 :set the range of temperatures
for setting the set point.
C
r2
Setpoint max.
value
r1
50
45
C
cc
Continuous cycle
period
0
15
1 (hours)
?
C
A0
Alarm and fan
differential
-20
+20
2
See chapter 5.2
F
AH
Alarm maximum
temp.
-50
+99
10
See chapter 5.2
C
Ad1
Delay for high and
low temp. alarm
0
199
30
Delay for high temperature alarm when
power on just before. When alarm condi-
tion is achieved but power on just before ,
the timer start to count for a specify value
(Ad1). Only the time elapsed, alarm relay
can be active
5.1.3
Parameter navigation
The operating parameters, modifiable using the key-
pad, are divided into two types: frequent (type F) and
configuration (type C). Access to the latter is pro-
tected by password (default= 22) to prevent acciden-
tal or un-authorized modifications.
Accessing the type F parameters:
Press the SET button for more than 3 s (if there
are active alarms, mute the buzzer), the display
shows the parameter code „PS‟ (password);
use the UP and DOWN buttons to scroll the pa-
rameters. The LED corresponding to the catego-
ry of parameters will be on (see parameters list)
press SET to display the value associated with
the parameter increase or decrease the value us-
ing the UP or DOWN button respectively;
press SET to temporarily save the new value and
display the parameter again; repeat the proce-
dure for any other parameters that need to be
modified;
press the SET button for more than 3 s to per-
manently save the parameters and exit the pa-
rameter setting procedure.
Accessing the type C parameters:
Press the SET button for more than 3 s (if there
are active alarms, mute the buzzer), the display
shows the parameter code “PS” (password);
