| Register number | Address | Description | Data format | Notes |
|---|---|---|---|---|
| 0x2049 | 0800 | Device status | 16-bit |
0 = Status OK. 1 = Critical error. 2 = Error. 4 = Warning. |
| 0x2050 | 0801 | CO2 status | 16-bit |
0 = Status OK. 2 = CO2 reading not reliable. Appears during transmitter start-up. 256 = Measurement not ready. Appears during transmitter start-up. |
If several errors are active at the same time, the Modbus error code register contains the sum of currently active error codes.