CONTENTS
SPC stands for statistical process control and is a method of using historical data to determine when a process is no longer operating within its normal parameters. XSPOC uses SPC to help find when runtime, cycles and other parameters are operating in an abnormal fashion. By using SPC, upper and lower control limits are established on these parameters that define a normal operating range. When the given parameter falls outside of the normal range, the system can alert the user to this abnormal condition through exception groups and alarms. SPC uses a calculation involving standard deviation, which looks at the amount of change between consecutive data points.
SPC is a much more efficient way to find system problems than the old method of manually setting these limits. SPC not only performs automatic alarm limit settings, but it also sets limits for wells based on that individual well's performance. Wells that have widely varying data will automatically have broader control limits calculated than those that have consistent data.
In XSPOC, SPC control limits are automatically calculated on several key parameters. These control limits are displayed on the trend graphs, and violations of these control limits can be observed through color coding on the group status screen and through exception groups.