TM_i-BX(-N)_NC05_00_06_20_EN
MEHITS S.p.A.
●
TECHNICAL MANUAL
Version NC05 - Translation of the Original Instructions
42
4.9.2.2
Regulation based on the external temperature up to version NC04.00 relC40 (not on three-phase i-BX-N units).
external T [°C]
100%
1407
Speed [%]
High Speed
(131T)
Min Speed
(131R)
1409
1408
1409
4.9.2.3
Regulation based on the external temperature starting from version NC04.00 relC50
external T [°C]
100%
1407
Speed [%]
High Speed
(131T)
Min Speed
(131R)
1409
1408
1409
1409
1436
Supermin Speed
(132I)
The parameters for the regulation based on the external temperature are only visible i
n Chiller mode and with fan regulation set to “EXTERNAL
TEMP.” (parameter
1406
).
4.9.3
ACTIVATION OF THE PRESSURE SAFETY CONTROL
With condensation fan speed regulation based on the external temperature and any regulation speed (SUPERMINIMUM, MINIMUM, HIGH), when
the condensation pressure exceeds the value given by parameter
1434
the fan automatically switches to the next higher speed step.
As soon as the pressure value falls below the value represented by the difference between the values of parameters
1434
–
1435
, the fan returns to
the step of the corresponding external temperature.
Example of pressure safety control:
if based on the external temperature the fan operates at MINIMUM speed, causing the pressure to rise above safety parameter
1434
, the fan then
switches to the next higher fan speed (in this case HIGH).
The fan will keep this speed until the pressure falls back below the pressure value given by the difference between parameters
1434
-
1435
At this point, the fan will return to the MINIMUM speed value.
For the default values of the various parameters, see the parameters table
