BAC_HX_01

Functional description

This template is used to calculate the dew point temperature, the specific enthalpy, the wet bulb temperature, and the absolute humidity.
The temperature, the relative humidity and the barometric pressure are required for calculating these parameters.

Interface

Block diagram

VAR_INPUT

rT       : REAL;
rPhi     : REAL;

rT: Current temperature value [°C]

rPhi: Current relative humidity value [%]

VAR_OUTPUT

rHumAbs   : REAL;
rDewPnt   : REAL;
rTWet     : REAL;
rE        : REAL;

rHumAbs: Calculated value Absolute humidity g water per kg dry air [g/kg]

rDewPnt: Calculated value Dew point temperature [°C]

rTWet: Calculated value Wet bulb temperature [°C]

rE: Calculated value Enthalpy [kJ/kg]

VAR CONSTANT

PLT_NUM    : BYTE := 1;

PLT_NUM: all alarms and events of all plant components within a controller are included in a global alarm and event list. The assignment of events and alarms to a plant is defined by the assignment of a PLT_NUM plant number.
The recording and processing of an alarm from an aggregate or a device takes place within the templates by means of the alarm function block FB_BA_Alarm.
The evaluation of the alarms of a plant, e.g. for the generation of a collective message or for plant shutdown in case of relevant faults, takes place within the template BAC_PltAlm_01 by means of the function block FB_BA_AlarmPlt.
The evaluation of different plant events within the templates of a plant, takes place within the template BAC_PltComnMsg_01 by means of the function block FB_BA_ComnMsg.

Important! The assignment and evaluation of the alarms and events of a plant can only be done correctly if all templates of a plant have the same plant number!

The plant number can be assigned in the Project Builder in the parameter menu for the templates or via a column in the Excel import.

Program description

Version history