classConventions

Conventions

Extends from Modelica.Icons.Information (Icon for general information packages).

Information

Control point connections

Inside a template class, the connect clauses involving control points typically do not have any graphical annotation and are therefore not rendered as connection lines in the diagram view. Those connect clauses are grouped together in a dedicated section of the equation section of each class, namely /* Control point connection - (start | stop) */.

Definitions

System

We adopt the definition hereafter from ASHRAE (2021).

A set of components is a system if they share a load in common (i.e., collectively act as a source to downstream equipment, such as a set of chillers in a lead/lag relation- ship serving air handlers).

  • Each air handler constitutes its own separate system because it does not share a load (terminal unit) in common with the other air handlers.
  • Each VAV box constitutes its own system because it does not share a load (conditioned space) in common with the other VAV boxes.

Abbreviations

The following abbreviations are used in that package.

AbbreviationDescription
AIAnalog input (integer or real)
AFMSAirflow measuring station
AHUAir handling unit
AOAnalog output (integer or real)
CHWChilled water
CWCondenser water
DHWDomestic hot water
DIDigital input (Boolean)
DODigital output (Boolean)
DOASDedicated outdoor air system
DPDifferential pressure
HHWHeating hot water
OAOutdoor air
VAVVariable air volume
VFDVariable frequency drive

References

  • ASHRAE, 2021. Guideline 36-2021, High-Performance Sequences of Operation for HVAC Systems. Atlanta, GA.