Siemens BACnet ATEC 125-5050 - Manual (Page 14)

Chapter 2 – Applications
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Siemens Industry, Inc.
BACnet ATEC Owner's Manaul
125-5050, Rev. AA 4/20/2010
Chapter 2 – Applications
Basic Operation
The BACnet ATEC provides Direct Digital Control (DDC) for Variable Air Volume (VAV)
terminal box applications. Temperature control varies with the application. If present,
heating can be provided by hot water, up to three stages of electric reheat, or optional
baseboard radiation.
Sequencing Logic (optional)
This application has the additional capability to sequence the flow and mechanical
heating when heated supply air is available.
Control Temperature Setpoints
The controller maintains a specified temperature setpoint based on Day/Night mode, or
the heating/cooling mode, or the setpoint dial (if used).
Day/Night Mode
The controller maintains the specified day setpoint temperature during daytime hours
and the specified night setpoint at night.
Night Mode Override Switch
If the ROOM TEMPERATURE SENSOR has an override switch, it can be used to
command the controller into day mode for an adjustable period of time. This only
affects a controller in night mode.
Control Loops
Temperature Loop – Heating Loop – Cooling Loop
Maintain temperature setpoint by changing the flow setpoint or modulating the heat
source (valve/electric heat).
Flow Loop
Maintains flow setpoint by modulating the damper actuator.