Types of Master Station Accumulator
ClearSCADA supports these types of master station, or server-side, Accumulator:
- Boolean Counter—A Boolean Counter calculates the number of times that its source changes from a False to True state, a True to False state, or both, over a specified period. The value of a Boolean Counter increments by one each time that a monitored state change occurs.
- Delta—A ‘Delta’ is a small change between two successive sets of data. A Delta Accumulator calculates the sum of the differences in source value over a specified period. A Delta Accumulator is often used to accumulate another Accumulator’s data over a different calculation period (for instance, to integrate the data of an Accumulator that uses a one-hour End of Period reset, over a 24-hour period).
- Integrator—An Integrator Accumulator calculates the total value of its source over a specified period (time x value).
- Maximum—A Maximum Accumulator calculates the maximum value that its source reaches over a specified period.
- Mean—A Mean Accumulator calculates the average value of its source over a specified period. You can specify whether the average value is calculated as an Arithmetic Mean, or a Time-Weighted Mean.
- Minimum—A Minimum Accumulator calculates the minimum value that its source reaches over a specified period.
- Rate of Change—A Rate of Change Accumulator calculates the rate at which its source value changes over a specified period. You can specify whether the rate of change compares the present source value against the previous source value, or uses Linear Regression to calculate the rate of change value. A negative Accumulator value indicates that the source’s value is falling, a positive Accumulator value indicates that the source’s value is rising.
- Runtime—A Runtime Accumulator calculates the amount of time that its source is in a True or False state during a specified period.
NOTE: Some types of outstation and scanner support Accumulators that reside locally at the outstation or scanner. For information on configuring such Accumulators, see the driver-specific documentation.