SPC — Control Charts (Is the Process Stable?)

A control chart watches a measurement over time and asks one question: is the process behaving normally, or did something change?

The I-chart (Individuals) plots each value and draws three lines:

Center line (green) = the average
UCL / LCL (red dashed) = upper & lower control limits, set at average ± 3σ

A point inside the limits is normal, expected variation — leave it alone. A point outside (or 8 in a row on one side) means a real change happened: a machine setting, a material batch, an operator, something worth investigating. SenSight marks those points red.

This is different from regression: SPC doesn't predict — it monitors one variable and flags the unusual.

Try it in the app

Try: Load a sample dataset → open the SPC tab. It runs automatically. Click a red (out-of-control) point on the chart — it opens an evidence note so you can record WHY that point was unusual.

SPC — Control Charts (Is the Process Stable?)

Run this on your own data

Why More Samples Improve Accuracy

Process Capability (Cp / Cpk)