Application

Room Automation Overview
Sequence of Operation – Summary
29
Siemens Industry, Inc.
Application Note
A6V11692053
Smart Infrastructure – Building Products
2019-04-01
Room Automation Overview
To ensure building controls can be optimized by central systems, primary systems
and individual room automation, it is essential that:
⚫ Individual BACnet objects are grouped together to facilitate optimization of
building systems.
⚫ Room operating functions are governed by the following room automation
operating modes: Room operating mode, Plant operating mode, and HVAC
device mode.
Room and Room segments
An application type is composed of various modules (application functions, AF) that
coordinate common functions and control devices. There are two general, large
collections of these application function; one named Room and the other Room
segment . This is helpful to know when you are trying to find and use various
features.
Depending on the application being used and its supported features, the Room AFs
provide coordination between various control devices and functions such as:
⚫ Plant operation mode
⚫ Room operation mode
⚫ Setpoint determination
⚫ Room cooling PID or Staged controller
⚫ Room heating PID or Staged controller
⚫ Room ventilation controller
⚫ Dehumidification PID controller
⚫ Heating/cooling state determination
The Room segment application functions control individual HVAC devices (for
example, heating coil, supply damper, and so on). Although a room usually has only
one room segment, multiple segments can be controlled and coordinated by a
single room.
Grouping
To manage these many entities and to facilitate central control functions, a
grouping mechanism has been applied to organize these functions by enabling
group collaboration, (that is, the data exchange between the central control
functions (group masters) and individual entities (group members).
Room and Room segment groups allow the central control and coordination of
different building systems, zones, areas. Typical central control functions are:
⚫ Central operating mode – from operating station or a scheduler, distributed to
connected rooms.
⚫ HVAC emergency – coordinates emergency functions in zones and controls the
HVAC devices according to the emergency mode.
⚫ Central HVAC functions – collects demand signals from rooms using grouping
mechanism and provides the setpoint and supply chain demand to the central
plants (for example, chilled water, hot water or air handling unit). DXRs can
also be used without leveraging central functions by programming at the
supervisory controller.