Easy BACnet
  1. Home
  2. BACnet points lists
  3. Siemens
  4. BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)

Laboratory VAV controller (fume hood) · BACnet points list

Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) BACnet points list

Updated 6 November 2026

Short answer

Application 6740 runs a constant volume or two-position fume hood on a Siemens BACnet programmable fume hood controller over BACnet MS/TP. It modulates the hood exhaust damper to hold a high or low exhaust airflow setpoint (EXH HI STPT / EXH LO STPT), picked by DI 2 or the left display button. It raises low/high flow warnings and alarms against the setpoint, has an emergency purge mode, and sends a 1-10 V exhaust flow signal on AO 2.

This page lists 73 BACnet objects for the Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) — 65 of them writable — with each object’s type, instance number, name, engineering units and access. It is re-typed from Siemens’s own free documentation, linked below.

Manufacturer
Siemens
Model
BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)
Equipment
Laboratory VAV controller (fume hood)
Equipment type
VAV boxes & fan coils
BACnet objects
73 (65 writable)
Transport
BACnet MS/TP
Firmware
Not stated
Also known as
Application 6740, App 6740, Siemens fume hood controller, Siemens FHC, two-position fume hood, constant volume fume hood
Source document
BACnet Programmable Fume Hood Controller 2-Position Constant Volume with Damper, Application 6740, Application Note · 140-1341 · rev. 2015-11-09
Download CSV 73 rows Download EDE B.I.G.-EU JSON Manufacturer PDF ↗ Compare with your scan Download Easy BACnet Mobile App Google Play

Reference only, provided as-is: verify against Siemens’s current documentation and the live device before use. Not official Siemens information. Terms of use.

BMS integration notes: Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)

Integration in brief

Address the controller on the BACnet MS/TP trunk (manually or with auto addressing) and set STARTUP MODE to normal. The BMS can select high or low flow with ODP STPT SW (BO 22), adjust the two exhaust setpoints, and reads exhaust airflow, the active setpoint and the alarm points.

Minimum points to map

The short list most integrators start with — enough to run the unit from a BMS. Map more as the job needs.

ObjectNameWhyAccess
BO 22ODP STPT SWHI = high exhaust setpoint (also set by DI 2)Command
AO 80EXH HI STPTHigh exhaust airflow setpoint, cfmCommand
AO 81EXH LO STPTLow exhaust airflow setpoint, cfmCommand
AI 31EXH VOLMeasured hood exhaust airflow, cfmRead
AO 82EXH STPTActive exhaust airflow setpoint, cfmCommand
BO 5LOW ALMLow flow alarmCommand
BO 6HIGH ALMHigh flow alarmCommand
BO 7EMER ALMEmergency purge alarmCommand
BO 8GEN FAILUREGeneral failure (sensor or hardware)Command

Enable & remote start

No enable point: the controller runs its sequence once STARTUP MODE (AO 21) is 0. The flow setpoint is high when DI 2 or the left display button (ODP STPT SW, BO 22) is HI.

Network setup

Watch out for

Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) BACnet objects

Type: AI, AO, AV, BI, BO, BV, MI/MO/MV (multi-state) · Access: Read read-only, Write writable, Command writable with a priority array.

Note: the source document has no read/write column, so access here is inferred from the object type (inputs read-only, values writable). Confirm on the live controller before writing.

73 of 73 shown
Type
Access
Show
Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) BACnet Points List
DescriptionStates
AO1CTLR ADDRESSController MS/TP addressCommand
AO2APPLICATIONApplication number running in the controllerCommand
BOmin5LOW ALMLow flow alarmCommand0=OFF, 1=ON
BOmin6HIGH ALMHigh flow alarmCommand0=OFF, 1=ON
BOmin7EMER ALMEmergency purge alarmCommand0=OFF, 1=ON
BOmin8GEN FAILUREGeneral failure (sensor or hardware)Command0=OFF, 1=ON
AO10HI ALM LMTHigh flow alarm limit, % of setpoint%Command
AO11HI WARN LMTHigh flow warning limit, % of setpoint%Command
AO12LOW WARN LMTLow flow warning limit, % of setpoint%Command
AO13LOW ALM LMTLow flow alarm limit, % of setpoint%Command
AO14EMER TIMEREmergency full-open timesCommand
AO15EMER STPTEmergency flow, % of the exhaust setpoint%Command
BO16LOW WARNLow flow warningCommand0=OFF, 1=ON
BO17HIGH WARNHigh flow warningCommand0=OFF, 1=ON
AO18ALARM TIMEDelay before a warning or alarm is setsCommand
BO19ALM AKNLGAlarm silenced from the display panelCommand0=OFF, 1=ON
BO20OCC.UNOCCOccupied/unoccupied modeCommand0=OCC, 1=UNOCC
AO21STARTUP MODENormal, decommission or startup mode (code)Command
BOmin22ODP STPT SWHigh/low flow select from the display buttonCommand0=HI, 1=LO
BO23RIGHT SWITCHRight display panel buttonCommand0=OFF, 1=ON
AImin31EXH VOLMeasured hood exhaust airflowcfmRead
AO32FLOW COEFAirflow pickup coefficientCommand
AO33DUCT AREAExhaust duct areaft²Command
AO34TRANS RANGEPressure transmitter rangeinH2OCommand
AO35LINEAR FL RGRange of a linear flow inputcfmCommand
AI36AVS2 PRESSAir velocity sensor 2 pressureinH2ORead
BI37DI2 STPT SWHigh/low flow select input on DI 2Read0=HI, 1=LO
BI38DI 6Digital input 6Read0=OFF, 1=ON
AO39AO 1Analog output 1VCommand
AO40AO 3Analog output 3VCommand
BO41EXTN DO1Damper actuator extend output on DO 1Command0=HOLD, 1=EXTN
BO42RETC DO2Damper actuator retract output on DO 2Command0=RETC, 1=HOLD
BO43DO 3Digital output 3Command0=OFF, 1=ON
BO44DO 4Digital output 4Command0=OFF, 1=ON
BO45HI.LOW DO5High/low flow status output on DO 5Command0=HI, 1=LO
BO46DECOM DO6Decommission output on DO 6Command0=OFF, 1=ON
BO47ALARM DO7Local alarm output on DO 7Command0=OFF, 1=ON
BO48AUTOZERO DO8Autozero module output on DO 8Command0=OFF, 1=ON
AI49AI 3Spare analog input 3VRead
AI50AI 4Spare analog input 4VRead
AI51AI 5Spare analog input 5kΩRead
BO56DI 4Binary output listed as DI 4 in the point tableCommand0=OFF, 1=ON
AO58DMPR CMDExhaust damper drive command (-100 to 100)%Command
BO59INVERT DO2Invert the DO 2 outputCommand0=NO, 1=YES
BO60AVS FAILMODEDamper action if the air velocity sensor failsCommand0=HOLD, 1=OPEN
AO61EXH P GAINExhaust flow loop proportional gainCommand
AO62EXH I GAINExhaust flow loop integral gainCommand
AO63EXH D GAINExhaust flow loop derivative gainCommand
BO78STARTUP DI4Startup mode input on DI 4Command0=NO, 1=YES
AOmin80EXH HI STPTHigh exhaust flow setpointcfmCommand
AOmin81EXH LO STPTLow exhaust flow setpointcfmCommand
AOmin82EXH STPTActive exhaust airflow setpointcfmCommand
AO89EXH SIG AO2Exhaust flow signal out on AO 2VCommand
AO90AO2 RANGEExhaust flow at 10 V on AO 2cfmCommand
AO91AO2 DEADBANDDeadband for the AO 2 flow signal%Command
AO92AO2 V MINMinimum AO 2 output voltageVCommand
BO94CAL AIRStart air velocity sensor calibrationCommand0=NO, 1=YES
AO95CAL SETUPCalibration setup codeCommand
AO96CAL TIMERHours between automatic calibrationshCommand
AI97AVS1 PRESSAir velocity sensor 1 pressureinH2ORead
AO98LOOP TIMEControl loop intervalsCommand
AO99ERROR STATUSController error status codeCommand
AO106DISPLAY WTDisplay smoothing weight%Command
AO107DISPLAY RESChange needed to update the displaycfmCommand
BO108BLANK DSPLYBlank the operator display panelCommand0=OFF, 1=ON
BO109LAMP TESTTest the display lampsCommand0=OFF, 1=ON
BO110ENG UNITSDisplay in English or SI unitsCommand0=ENG, 1=SI
AO121HI LIMITFeedback loop high limit (not described in the guide)Command
AO122LO LIMITFeedback loop low limit (not described in the guide)Command
BO123EMER DI6Remote emergency purge input on DI 6Command0=OFF, 1=ON
BO125ODP DISPLAYDisplay shows airflow or modeCommand0=MODE, 1=CFM
AO126AVE EXH VOLAveraged exhaust airflow shown on the displaycfmCommand
BO127PPCL STATEPPCL program loaded or emptyCommand0=EMPTY, 1=LOADED
Object ID lookup: Siemens Fume Hood Controller 6740 point IDs by name

Integration notes

Check it against the live device. A points list tells you what the controller can expose; the unit in front of you may differ by firmware or installed options. This list is provided as-is for reference only and may contain mistakes — confirming it before you write, map or commission anything is up to you (terms). Easy BACnet scans a network for BACnet IP devices from an Android phone, reads every object on the BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) and exports what it actually has to Excel — free. New to BACnet? Start with what a BACnet points list is and what the object types mean.

Questions about the Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)

How many BACnet points does the Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) have?

This list has 73 BACnet objects: 6 analog inputs, 36 analog outputs, 2 binary inputs, 29 binary outputs. The exact set on a given unit depends on its firmware, installed options and configuration.

Which Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) BACnet points are writable?

65 of the 73 objects accept a write. Points marked Command have a priority array: a write holds until it is released, so release it back to automatic when you are done. The source has no read/write column, so this is inferred from object type.

Where is the official Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper) BACnet documentation?

The source is BACnet Programmable Fume Hood Controller 2-Position Constant Volume with Damper, Application 6740, Application Note (140-1341), revision 2015-11-09, published free by Siemens at https://sid.siemens.com/api/khub/documents/LFSSQ8f~mpjer3CY5qEURw/content.

What are the minimum BACnet points to integrate the Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)?

Start with BO 22 ODP STPT SW (HI = high exhaust setpoint (also set by DI 2)); AO 80 EXH HI STPT (High exhaust airflow setpoint, cfm); AO 81 EXH LO STPT (Low exhaust airflow setpoint, cfm); AI 31 EXH VOL (Measured hood exhaust airflow, cfm); AO 82 EXH STPT (Active exhaust airflow setpoint, cfm); BO 5 LOW ALM (Low flow alarm); BO 6 HIGH ALM (High flow alarm); BO 7 EMER ALM (Emergency purge alarm); BO 8 GEN FAILURE (General failure (sensor or hardware)).

How do I enable BMS control of the Siemens BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)?

No enable point: the controller runs its sequence once STARTUP MODE (AO 21) is 0. The flow setpoint is high when DI 2 or the left display button (ODP STPT SW, BO 22) is HI.

How do I check these points on the real BACnet Programmable Fume Hood Controller - Application 6740 (2-Position Constant Volume with Damper)?

Scan the network with a BACnet IP browser such as Easy BACnet, open the device and compare its object list with this table. Anything missing is usually an option that isn't installed or a point that is disabled in the controller's configuration.

More Siemens BACnet points lists

Source: BACnet Programmable Fume Hood Controller 2-Position Constant Volume with Damper, Application 6740, Application Note · 140-1341 · rev. 2015-11-09. Object names, instances and units are reproduced as published; descriptions are our own.