Siemens 125-5050 owner manual Applications, Basic Operation

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Chapter 2 – Applications

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.
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Siemens Industry, Inc.	BACnet ATEC Owner's Manaul
125-5050, Rev. AA	4/20/2010

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Contents Siemens BACnet Atec Siemens Industry, IncPage FCC Regulations Service StatementCopyright Notice To the Reader CreditsTable of contents Using the Controller as a Point Extension Device Manual Conventions How To Use This ManualManual Organization Getting Help Manual SymbolsWhere to Send Comments BACnet Atec Electronic Output Applications Product OverviewOrdering Notes Application DescriptionAnalog Hardware InputsHardware Outputs DigitalPower Wiring ApplicationController LEDs Communication WiringController LED Indicators IndicationDuct Temperature Sensor Temperature SensorsRoom Temperature Sensor Related EquipmentApplications Basic OperationDamper Status Operation Heating and Cooling SwitchoverCalibration Fail-safe OperationElectric Reheat Modulate Damper During Heating Mode optionalHot Water Reheat Application 2860 VAV Cooling Only Application 2861 VAV Cooling or HeatingElectric Heat Interlock Application 2863 VAV with Hot Water ReheatBaseboard Radiation Application 2864 VAV Series Fan Powered with Electric Reheat Fan OperationInsert TEC2564CD Insert TEC2566CD Using the Controller as a Point Extension Device Application 2897 Slave ModeUsing Auxiliary Points Insert TEC2567CDApplications Point Database Descriptor Address Application DescriptionDescriptor Address1 Descriptor Address1 Application Description VLV1 POS MTR SetupVLV POS MTR2 TimingFlow Switch LimitSwitch Time CTL Flow MINCAL Timer Switch DbandCAL Setup SetupPreventive Maintenance Chaper 4 TroubleshootingBasic Service Information Safety Features Controller LEDsGlossary Lps Override switchField panel LoopoutTerminal Equipment Controller Slave modeStand-alone control UnbundleIndex Duct temperature sensor, 15 RTS Index Communication wiring Wiring Power wiring 125-5050, Rev. AA