Thermokon · Sensor
thevios 3 OCC Lum rH IR room sensor (RS485 Modbus) Modbus register map
Default configuration
- Protocol
- RS485
- Port
- 502
- Unit ID
- 1
- Addressing
- 0-based
- Byte order
- Big endian
- Word order
- High word first
- Baud rate
- 38400
- Parity
- Even
- Data bits
- 8
- Stop bits
- 1
This device has an RS-485 interface. Reach it through a Modbus RTU-to-TCP gateway, configured with the factory serial settings above.
Register map
| Address | Count | Name | Type | Unit | Scale | Access |
|---|---|---|---|---|---|---|
| 100 | 1 | Movement Presence detection value of the PIR sensor. | Int16 | - | 1 | R |
| 101 | 1 | Temperature Unit system SI, resolution 0.1 °C. With unit system 2 (imperial) the same register holds the value in °F with 0.1 resolution. | Int16 | °C | 0.1 | R |
| 102 | 1 | Temperature IR Radiant temperature, only on the thevios 3 OCC Lum rH IR. Resolution 0.1 °C (0.1 °F in imperial mode). | Int16 | °C | 0.1 | R |
| 103 | 1 | Relative humidity Resolution 1 percent RH. | Int16 | % | 1 | R |
| 104 | 1 | Absolute humidity Unit system SI only; 0.1 g/m3. In imperial mode the register holds gr/ft3. | Int16 | g/m3 | 0.1 | R |
| 105 | 1 | Enthalpy Unit system SI only; 0.1 kJ/kg. In imperial mode the register holds BTU/lb. | Int16 | kJ/kg | 0.1 | R |
| 106 | 1 | Dew point Unit system SI only; 0.1 °C (0.1 °F in imperial mode). | Int16 | °C | 0.1 | R |
| 110 | 1 | Luminosity Resolution 1 lux. | Int16 | lux | 1 | R |
| 111 | 1 | Temperature MIX Mixed temperature from the internal and IR sensor. Resolution 0.1 °C (0.1 °F in imperial mode). | Int16 | °C | 0.1 | R |
| 118 | 1 | Sensor error Bit-coded internal sensor error; 0 = no error. | Binary | - | 1 | R |
| 119 | 1 | LED lighting colour 0 = off (default), 1 = red, 2 = green, 3 = yellow, 4 = blue, 5 = magenta, 6 = cyan, 7 = white. Not stored: the register has to be rewritten after a restart. | UInt16 | - | 1 | RW |
| 2100 | 1 | Unit system 1 = SI (default), 2 = imperial. Changing it does not adjust the upper and lower limits of the measured values. Stored in EEPROM. | UInt16 | - | 1 | RW |
| 3030 | 1 | Movement sensitivity Default medium. Adjusted through the app; a restart is required after a change. | Int16 | - | 1 | RW |
| 3031 | 1 | Movement delay time Default 600 s. | Int16 | s | 1 | RW |
| 3032 | 1 | PIR LED mode 0 = LED permanently off, 1 = LED on/off (activated by movement), 2 = walk test. | Int16 | - | 1 | RW |
| 3111 | 1 | Temperature offset Default 0, resolution 0.1 °C. Stored in EEPROM. | Int16 | °C | 0.1 | RW |
| 3211 | 1 | Temperature IR offset Default 0, resolution 0.1 °C. Stored in EEPROM. | Int16 | °C | 0.1 | RW |
| 3311 | 1 | Offset relative humidity Default 0, resolution 1 percent. Stored in EEPROM. | Int16 | % | 1 | RW |
| 4012 | 1 | Luminosity lower range limit Default 0, resolution 1 lux. | UInt16 | lux | 1 | RW |
| 4013 | 1 | Luminosity upper range limit Default 20000, resolution 1 lux. | UInt16 | lux | 1 | RW |
| 4023 | 1 | Luminosity calibration factor Resolution 0.001. Field calibration: reference reading divided by the thevios 3 reading, multiplied by 1000 (the document's example: 1200 lux reference against 600 lux measured gives factor 2000). | UInt16 | - | 1 | RW |
| 17000 | 1 | Device address (slave ID) Bus address 1...247. Default 1. Changing it takes effect immediately and can break the connection. | UInt16 | - | 1 | RW |
| 17001 | 2 | Baud rate 9600, 19200, 38400, 57600, 76800 or 115200. Default 38400. | UInt32 | - | 1 | RW |
| 17003 | 1 | Parity Even, odd or none. Default even. The number of stop bits follows the parity: one stop bit with even or odd parity, one or two configurable stop bits with no parity. | UInt16 | - | 1 | RW |
| 17004 | 1 | Stop bits Default 1 stop bit. Only configurable when parity is none. | UInt16 | - | 1 | RW |
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Related guides
Notes
Source: Thermokon Sensortechnik 'RS485 Modbus Manual - thevios 3', revision C dated 27.10.2026 with revision history entries for versions 1.5/1.6 (default communication settings added 06.02.2026), vendor URL above; the manual covers 'thevios 3 RS485 Modbus' in the OCC Lum, OCC Lum rH and OCC Lum rH IR variants. Factory bus settings from section 1.6 'Default communication settings': bus address 1, 38400 baud, even parity, 1 stop bit (the micro-USB/uConfig port uses 115200 8N1 and is not the bus). Addressing: the manual states that 'all registers listed below are holding registers that can be accessed via function codes 3, 6 and 16' and that 'the Address column shows the data address of the respective register'; the numbers are stored unchanged as the wire address, i.e. zero_based - the configuration block at 17000/17001 is the device's own slave-ID/baud/parity/stop-bit block, which matches the values quoted for 1.6. The register list starts at 100 (movement) and 101 (temperature) and the layout only makes sense as protocol addresses. Only measured values, offsets, configuration and the bus settings are included. Left out on purpose: the device identification strings (registers 1200-1223 device description, 1230-1235 production date, operating hours counter and firmware, 17001 as a u32 in the vendor's table is entered here as the two-register baud rate row) and register 2102-2105 (maintenance and calibration countdown/interval), which are service counters without a unit; the manual's own 'Measurement variable' tables are the ones used, and availability depends on the model (for example the radiant Temperature IR at 102 only exists on the OCC Lum rH IR). Values in imperial mode share the same registers, so the units in this map describe the factory SI setting (register 2100 = 1).