Exponentially Weighted Moving Averages (EWMAs) - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 13.1

Shows how well the setpoint is maintained over time.

The Absolute Error EWMA is the absolute value of the calculated setpoint minus the present value of the controlled variable (for example, temperature or flow). These values are calculated in the units of the controlled variable. The moving average calculation for this value is performed at the effective period of the PID.

Example: If this value increases in reference to the type of loop under control, the increase may indicate a control or mechanical system issue.

Shows whether output devices are being exercised excessively.

The Absolute Effort EWMA is the absolute value of the change in the present value from one execution of the PID to the next. These values are calculated as percentages. The moving average calculation for this value is performed at the effective period of the PID.

Example: If this value increases more than 5 to 10%, the increase may indicate excessive controlled device movement.

Indicates whether you are above or below the error as above or below the setpoint.

The Error EWMA is the controlled variable setpoint minus the present value of the controlled variable. These values are calculated in the units of the controlled variable. The moving average calculation for this value is performed at the effective period of the PID.

Example: If this value increases or decreases in reference to the type of loop under control, the value change may indicate a control or mechanical system issue. If a loop is cycling above and below its setpoint, the XXX-ERROR value tends to be close to zero, which is why we recommend using the XXX-ABSERROR value instead.