Use the Control Limit Calculator to determine the upper and lower control limits for your process based on the mean, standard deviation, and sample size.

Understanding Control Limits

Control limits are essential in statistical process control (SPC) as they help monitor the stability of a process. They are calculated based on the process mean and standard deviation, providing a range within which the process variation is expected to occur. If the process data falls outside these limits, it indicates that the process may be out of control and requires investigation.

How to Calculate Control Limits

The formula for calculating the upper control limit (UCL) and lower control limit (LCL) is as follows:

UCL = μ + 3(σ / √n)
LCL = μ - 3(σ / √n)

Where:

  • μ = Process Mean
  • σ = Standard Deviation
  • n = Sample Size

By applying these formulas, you can effectively determine the control limits for your process, ensuring that it remains within acceptable variation levels.

Importance of Control Limits

Control limits play a crucial role in quality control and process management. They help identify trends, shifts, or any unusual patterns in the data that may indicate potential issues. By regularly monitoring the process against these limits,