What is the meaning of the Quality value into Trend Buffer CSV file?
What to know
The CSV file obtained from a Dump Trend Buffer operation is composed by many items. Quality field reports information about tag communication quality at the moment the samples has been taken.
Information is coded according OPC DA standard; it is represented in a byte data (8 bits) currently defined in form of three bit fields; Quality, Sub status and Limit status. The 8 Quality bits are arranged as follows: QQSSSSLL
| Quality Code | Quality | Description |
|---|---|---|
| 0 | BAD | The value is bad but no specific reason is known |
| 4 | BAD | There is some server specific problem with the configuration. For example, the tag in question has been deleted from the configuration file (tags.xml). |
| 8 | BAD | This quality may reflect that no value is available at this time, for reasons such as the value may have not been provided by the data source. |
| 12 | BAD | A device failure has been detected |
| 16 | BAD | Timeout occurred before device responded. |
| 24 | BAD | Communications have failed. |
| 28 | BAD | There are no data found to provide upper or lower bound value (trend interface specific flag). |
| 32 | BAD | No data have been collected (i.e. archiving not active. Trend interface specific flag). When the HMI return online after a reboot or from a condition where sampling stopped, a sample with quality value 32 is added to indicate this temporary offline status. |
| 64 | UNCERTAIN | There is no specific reason why the value is uncertain. |
| 65 | UNCERTAIN | There is no specific reason why the value is uncertain. (The value has ‘pegged’ at some lower limit) |
| 66 | UNCERTAIN | There is no specific reason why the value is uncertain. (The value has ‘pegged’ at some high limit.) |
| 67 | UNCERTAIN | There is no specific reason why the value is uncertain. (The value is a constant and cannot move.) |
| 84 | UNCERTAIN | The returned value is outside the limits defined for it. Note that in this case the “Limits” field indicates which limit has been exceeded but the value can move farther out of this range. |
| 85 | UNCERTAIN | The returned value is outside the limits defined for it. Note that in this case the “Limits” field indicates which limit has been exceeded but the value can move farther out of this range. (The value has ‘pegged’ at some lower limit) |
| 86 | UNCERTAIN | The returned value is outside the limits defined for it. Note that in this case the “Limits” field indicates which limit has been exceeded but the value can move farther out of this range. (The value has ‘pegged’ at some high limit.) |
| 87 | UNCERTAIN | The returned value is outside the limits defined for it. Note that in this case the “Limits” field indicates which limit has been exceeded but the value can move farther out of this range. (The value is a constant and cannot move.) |
| 192 | GOOD |
We suggest to refer to Jmobile Studio Help to get further informations regarding all the voices present into the CSV file dumped.
