Comparison control chart X – R, X – S and Max chart’s to monitor of water pH

Control charts are statistical tools used to keep watch on the stability of a process over time. It can be used to monitor the mean or variabilities’ changing of a process, which can indicate the need for corrective action. One type of control chart that monitors simultaneously the mean and variability of a process and this diagram has the advantage of being able to detect smaller changes in the process than traditional control charts is the Max chart control chart. The data consisted of 116 samples to monitor to monitor the water pH of a shrimp pond in Madura, Indonesia. This research, the X̄ – − R and X̄ – −S methods showed that 116 data points were in control and 0 data points were out of control. In contrast, the Max chart used α = 0.0027 method showed that 2 data points were beyond control limits and 114 data points were in control. This shows that pH of the pond water was stable most of the time, but there were two occasions where the pH changed significantly. One of the criteria for measuring a control chart is to measure how quickly the control chart can detect an out-of-control signal when a process change occurs. Early detection indicates the control chart is sensitive to process drift. The results of this research suggest that the Max chart is a sensitive tool for detecting the water quality of shrimp ponds. It can be used to detect changes in the water pH, which can help to ensure that the shrimp are living in a healthy environment.