Enhancing PI ProcessBook Trends with Banding and Zones: User Needs, Workarounds, and the Road Ahead

Visualization is at the heart of process data analysis. One common request from OSIsoft PI users is to enhance trends in PI ProcessBook with banding or zoning features—enabling engineers and operators to quickly see if values are within optimal, warning, or critical ranges. This blog synthesizes community feedback and explores feasible approaches and future directions for visualizing limit bands on trends in PI ProcessBook and beyond.

The Case for Trend Banding in PI ProcessBook

Traditional PI ProcessBook trends display time series data against static axes. While you can overlay limit lines by adding extra traces, users have called for more intuitive background indicator bands—much like the multistating available on other symbols. Banding visually segments trend areas, such as:

• High Limit (e.g., 85–100)
• Optimal Zone (e.g., 15–85)
• Low Limit (e.g., 0–15)

Shading these zones, possibly with transparency, provides instant situational awareness.

Customization and Data-Driven Banding

A common enhancement request: allow band limits to be dynamic, tied to PI tags or dataset values—which may themselves change over time. This raises two primary needs:

1. Dynamic Band Values: Configure bands that reflect changing process limits, enabling real-time visuals.
2. Customization: Users want finer control over the trend background, including which area to shade, control over transparency, and behavior with multiple y-axes/scales.

Workarounds with VBA: Creative, but Not Seamless

Resourceful users have employed VBA scripts to add colored rectangles behind the trend, simulating banding. However, this workaround depends on:

• Ability to query the trend's axis area (the drawing region between axes), to accurately place rectangles or lines.
• Proper layering and alignment, so that bands match trend data regardless of axis scaling or resizing.
• Managing transparency, especially when trends use multiple axes.

These hacks are functional but brittle, and each new display needs custom code and maintenance.

UI Pain Points: Markers and Value Attributes

Two recurring frustrations:

• Marker Space: Since ProcessBook v3, space is always reserved above the y-axis for markers (for annotations, data quality, etc.). On small trend objects, this reserved space is disproportionate. Users request per-trend (not global) control of marker space and title visibility.
• Value Attributes: The ability to hide value attributes exists, but is per-machine, not per-symbol or per-display—limiting flexibility in mixed-use environments.

Looking Forward: Coresight/PI Vision and Extensibility

While there are no immediate plans to retroactively add banding to ProcessBook, there's good news in the evolution of the PI platform:

• PI Coresight/PI Vision Trends: The next-generation PI Vision platform is being engineered with trend banding and extensibility in mind! Customization frameworks are a recognized community need, paving the way for user-defined visualization features.

Stay tuned for official announcements as PI Vision matures—trends are poised to become more visually informative and customizable than ever.

Conclusion

Trend banding is more than visual polish; it translates raw data into actionable insight by emphasizing operational zones. While creative VBA is today’s main workaround in PI ProcessBook, real progress toward native, robust banding features is on the horizon with the development of PI Vision. Until then, understanding both the limits of current tools and the available scripting tactics will help you get the most out of your PI data visualizations.

Are you leveraging banding or custom shading in your PI trends? Share your approach or wishlist for future releases below!