The Profile Plot card shows the shape of a linear sensor array and how that shape changes over time. Where a Graph card plots one point against time, a Profile Plot plots the whole run against position.
It suits instruments installed as a string along a line: ShapeArrays, in-place inclinometers, and distributed fibre optic sensing. Use it to see current shape, movement over time, change against a baseline, and where along the run that movement is happening.
Configure the installation, not the chart
The setup describes the physical installation. From that, the card works out the visualization for itself — how many profiles to draw, how to aggregate, how to scale the axes. You are not asked to configure those.
Spatial reference
Configure profile opens the spatial setup, where you describe how the array sits in the ground or on the structure.
| Setting | What it means |
|---|---|
| Measurement axis | How the run is represented in engineering space: depth, elevation, or distance. |
| Fixed end | Which end is the reference point, Near or Far. Near is the cable origin; Far is the terminal end of the string. |
| Coordinate unit | The unit the segment coordinates are given in. |
The Fixed end choice matters more than it looks. It is the end movement is measured against, so it should be the end you believe is stationary.
Segment coordinates
Each segment needs its position along the run. Where segments are evenly spaced, set an initial value and an interval and use Auto-fill to populate them all. Where they are not, enter the coordinates from the installation record.
Segment order is the order along the physical installation, not the order the devices happen to be listed in. A profile that reads as noise rather than a shape is usually segments out of order.
Data interpretation
| Setting | Options | Use |
|---|---|---|
| Calculation type | Cumulative or Incremental | Cumulative accumulates deformation from the fixed end and shows overall shape. Incremental shows each segment on its own and reveals localized movement. |
| Baseline | Relative to a baseline, or Absolute | Relative subtracts a reference state to show change. Absolute shows the shape as measured. |
| Metric and Unit | The measurement being profiled and the unit it is drawn in | Strain in microstrain, displacement, and so on. |
Cumulative and Incremental answer different questions from the same data. A gradual bow along the whole run stands out in Cumulative; a single segment moving stands out in Incremental. It is worth looking at both.
How much to draw
Plot count caps how many profiles are drawn, each one the state of the array at a point in time. Fewer may appear than you ask for, depending on what data exists in the dashboard's time range.
This is the setting to reach for when a card is unreadable. Twenty profiles across a week shows a trend; twenty across an hour shows noise. Adjust the dashboard time range and the plot count together rather than either alone.
Decimal precision controls the figures shown in tooltips and labels. Reduce it when readings are noisy and the extra digits are not telling you anything.
Reading it
Absolute mode answers "what shape is it now?". Relative to Baseline answers "what has changed since the baseline?", and for movement that is usually the more useful question.
If a profile looks inverted or anchored at the wrong end, check Fixed end before suspecting the data. If it reads as noise rather than a shape, check the segment coordinates.
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