FB_BA_RmTAdj

The function block FB_BA_RmTAdj is used for user adjustment of the room temperature setpoint. It shifts the setpoints at the input of a function block depending on an offset rRmTAdj, as shown in the following diagram. At the input fRmTAdj, the value of a resistance potentiometer or a bus-compatible field device, for example, can be used for the setpoint correction.

If the set value fRmTAdj is greater than zero, room temperature heating is desired: The Comfort Heating value is raised by the value fRmTAdj. At the same time, the values for Comfort Cooling and PreComfort Cooling are increased. If the value rRmTAdj is less than zero, a lower room temperature is requested. Analogous to the heating case, the values for Comfort Cooling, Comfort Heating and PreComfort Heating are now reduced by the value rRmTAdj.

Auto-correction

The temperature adjustment is intended for small corrections of the values. Although it is possible to enter any input values, a heating system will only work in a meaningful manner if the setpoints have ascending values in the following order:

• Protection Heating
• Economy Heating
• Precomfort Heating
• Comfort Heating
• Comfort Cooling
• Precomfort Cooling
• Economy Cooling
• Protection Cooling

Auto-correction works according to the following principle: Starting with the value Economy Heating, the system checks whether this value is smaller than the lower value of Protection Heating. If this is the case, the value for Economy Heating is adjusted to match the value for Protection Heating. The system then checks whether the value for Precomfort Heating is less than Economy Heating and so on, until the value for Protection Cooling is compared with the value for Economy Cooling. If one or several values were corrected, this is indicated with a TRUE signal at output bValCorr.

Inputs

VAR_INPUT
  fRmTAdj   : REAL;
  stSp      : ST_BA_SpRmT;
END_VAR

Outputs

VAR_OUTPUT
  bValCorr      : BOOL;
  fPrPrtcHtg    : REAL;
  fPrEcoHtg     : REAL;
  fPrPreCmfHtg  : REAL;
  fPrCmfHtg     : REAL;
  fPrPrtcCol    : REAL;
  fPrEcoCol     : REAL;
  fPrPreCmfCol  : REAL;
  fPrCmfCol     : REAL;
  stPrSp        : ST_BA_SpRmT;
END_VAR

Requirements