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BACnet instance calculator · GridSet BACnet gateway (Hub-4 Pro)
GPS Air GridSet BACnet Instance Calculator (Ports)
Free browser tool · nothing is uploaded · 5 November 2026
The smartIAQ Hub-4 Pro gives each of its four ports the same block of objects at port x 1000.
Instance = port x 1000 + offset, and object names start with 'Port N'. Port 3's CO2 is AI 3003 and its fan mode command is MV 3036.
GPS Air calculator
The calculator needs JavaScript. The formula and a worked example are below.
Which unit does this instance belong to?
How the numbers are built
instance = port x 1000 + offset
| Part | Meaning | Range |
|---|---|---|
| port | Hub-4 Pro port the device is plugged into | 1-4 |
| offset | Object offset | 1-61 |
Objects are created when a device first reports on a port, and only for the sensors and actuators that device has.
Worked example: port 3
The first objects for port 3 on the GridSet, worked out with the formula above:
| Object | Name (as printed) | What it is |
|---|---|---|
| AI 3001 | Port 1 Zone Temp | Zone temperature (only if device has temp_sensor) |
| AI 3002 | Port 1 Humidity | Relative humidity (only if device has humidity_sensor) |
| AI 3003 | Port 1 CO2 | CO2 level (only if device has co2_sensor) |
| AI 3004 | Port 1 PM2.5 | Particulate PM2.5 (only if device has particulate_sensor) |
| AI 3005 | Port 1 VOC | Volatile organic compounds (only if device has voc_sensor) |
| AI 3006 | Port 1 NOx | NOx index (only if device has voc_sensor) |
Source
Formula and objects from smartIAQ GridSet BACnet Integration Guide · GPS-050-57-R22-GSOL · rev. R22 (manufacturer document ↗), re-typed in our points list. Object names are shown as printed.
Check it against the live device. The calculator applies the formula from the manufacturer’s documentation; the gateway in front of you may expose fewer objects or use other numbers after a firmware change. Easy BACnet scans a network for BACnet IP devices from an Android phone and reads every object on them — a quick way to confirm one unit before you map a whole building.
Questions
How do I work out a GPS Air instance number?
Instance = port x 1000 + offset, and object names start with 'Port N'. Port 3's CO2 is AI 3003 and its fan mode command is MV 3036.
Why is a port missing objects?
The gateway only creates objects for the sensors and actuators the connected device actually has, and only after it first reports.
Is this GPS Air calculator official?
No. It applies the formula printed in GPS Air's own documentation to the points list in our library. Confirm the numbers against a scan of the live device before you map or write anything.
More instance calculators
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