| Value of bits 5...2 (decimal) | "UNCERTAIN" sub-status | Description |
|---|---|---|
| 0 | Non-specific | There is no specific reason why the value is UNCERTAIN. |
| 1 | Last usable value | The connection to the data source is still established, however the data source stopped updating the value for some reason. |
| 2 | Substitute value | A predefined value is used in case of an invalid value due to communication issues with the data source or a range violation. The reason for providing substitute values is configurable. |
| 3 | Initial value | A predefined value intended for the startup of the HMI system (or a sub-ordinate device) is used while not being able to provide values from the data source. |
| 5 | Range violation | The value lies outside the range defined by the min. and max. value. The limits define which direction (min. or max.) has been exceeded. |
| 6 | Sub-normal | A value derived from multiple values has less than the required number of good sources. This includes data aggregation by means of data compression algorithms. |
For further “UNCERTAIN” sub-status codes assigned by PLC/periphery only, refer to PROFIBUS-PA.