Regulation Based On The External Temperature Up To Version Nc04.00 Relc40 (Not On Three-Phase I-Bx-N Units); Regulation Based On The External Temperature Starting From Version Nc04.00 Relc50; Activation Of The Pressure Safety Control - Mitsubishi Electric i-BX-N Technical Manual

TM_i-BX(-N)_NC05_00_06_20_EN
4.9.2.2

Regulation based on the external temperature up to version NC04.00 relC40 (not on three-phase i-BX-N units).

Speed [%]
4.9.2.3

Regulation based on the external temperature starting from version NC04.00 relC50

Speed [%]
Supermin Speed
The parameters for the regulation based on the external temperature are only visible in 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
MEHITS S.p.A. ● TECHNICAL MANUAL
1409
100%
High Speed
(131T)
Min Speed
(131R)
1407
1409
100%
High Speed
(131T)
1409
Min Speed
(131R)
(132I)
1436 1407
1409
external T [°C]
1408
1409
external T [°C]
1408
42
Version NC05 - Translation of the Original Instructions