Vision Library+ / Guide
Data Quality
Vision Library+ can hide exact PI No Data results and warn operators when a live value has not received a recent event. These options are available only on symbols where the behavior is meaningful.
Overview
Vision Library+ can hide exact PI No Data results and warn operators when a live value has not received a recent event. These options are available only on symbols where the behavior is meaningful.
Supported symbols
| Symbol | Hide No Data | Stale warning |
|---|---|---|
| Value+ | Yes | Yes |
| Combo Chart+ | Yes | No |
| Linear Gauge+ | No | Yes |
| Radial Gauge+ | No | Yes |
| Alarm Sound+ | No | Yes |
Each symbol's Data Quality configuration shows only the settings it supports.
Hide No Data
Hide No Data applies only to the exact PI No Data state. It does not hide other bad values, system states, or errors, because those conditions can contain important diagnostic information.
- Value+: Hides the displayed value. In display-editing mode, a small placeholder keeps the hidden symbol selectable and configurable.
- Combo Chart+: Omits an empty series or a series whose available samples are all
No Data. Its legend and summary entries are also omitted. An isolatedNo Datasample in an otherwise valid series remains a gap.
This setting is useful on templated displays where some assets do not contain every configured attribute.
Stale warning
Stale warning shows an amber clock when a supported symbol is displaying a live current value whose source timestamp is older than Stale after. Hover over the warning to see the last event time, current data age, and configured threshold. Value+ adds these details to its normal symbol tooltip.
For Linear Gauge+ and Radial Gauge+, the warning appears when any displayed pointer is stale, and its tooltip identifies the affected data sources. Alarm Sound+ changes to an amber stale state; while stale, the old value is not evaluated as either Default or Alarm and no alarm audio is played.
Stale checking uses event timestamps. It does not detect a frozen sensor when PI continues writing newer events with the same value. Historical display time, custom-time or offset Value+ reads, and summary values are not evaluated as stale.
Choose a threshold longer than the expected event interval. Allow for scan frequency, PI exception and compression settings, and scheduled analysis intervals.
Local and global settings
By default, each symbol uses its own saved Data Quality settings. An administrator can enable a global override that enforces the site-wide values on every supported symbol with no per-symbol opt-out. The configuration pane indicates when the global override is active.
Enabling or disabling the global override does not overwrite the settings saved with a symbol. If the override is later disabled, the symbol resumes its saved local settings.
Troubleshoot chart data loading
Use these checks for Combo Chart+ and Asset Time Series Chart+ when history, summary values, or multi-state limits are unavailable.
Read the PI Vision log
Select the message icon in the PI Vision header. Its tooltip is PI Vision Messages. Find the message for the affected chart and data source, and read what failed and any server details. Select Download to save PIVisualization_log.txt when you need the complete log for support.
Check the reported condition
| Condition | What to do |
|---|---|
| A history refresh failed | In Default mode, which loads plot data, failed requests retry automatically as the display continues updating. Previously accepted history can remain visible when it still belongs to the same sources; it does not mean the refresh succeeded. If failures continue, ask an administrator to check PI Web API connectivity and your access to the named source. |
| A source or its metadata could not be loaded | Confirm the named attribute still exists and is the intended source. Use the actual server reason to distinguish missing data from permission or connection failures. Ask an administrator to check source access and metadata when the problem persists. |
| Recorded data reached a loading limit | Shorten the time range, or select Data Retrieval > Default for a sampled overview. Combo Chart+ can use plot data for that update after reaching its Recorded limit. Asset Time Series Chart+ does not silently switch retrieval modes. |
| Only summary cells or multi-state features are missing | These features load data separately from the chart history. Check the specific summary or limit error. An unavailable value, bad quality, or an unsupported numeric comparison can leave a dash or gap without a warning; it does not by itself indicate a failed request. |
Confirm the symbol time range as well as display time. A custom range or locked Time Bar can request a different period. Changing a time range does not fix a permission error, and summary and multi-state requests do not necessarily follow the same retry schedule as plot history.
Contact support
Include the display link, chart type, affected source name or path, time range and time zone, retrieval mode, and Vision Library+ version from About. Attach the downloaded PI Vision log and a screenshot showing the problem. State whether it affects one source or all sources and whether it continues after the next refresh.
