A control chart is a popular statistical tool for monitoring the quality of goods and services, and for detecting when the process goes "out of control" as early as possible. Samples from the process are taken every time interval, and their quality measured. Control charts are used to track the sample quality over time and detect any unusual behavior. Below are calculators that help you to easily obtain the control chart limits for different types of measurements.
|What is it for?
|Control Charts for Variables
|Compute limits for x, S and R control charts
|Control Charts for Attributes
|Compute limits for c, p, u and np
|Western Electric Company (WECO) Rules
|The detections of small shifts
|"Signal an alarm if 8 consecutive points fall on one side of the center line"