Totalizer Tags
The totalizer tag provides a means of accumulating the sum of another tag's (or calculation's) value over time. To put it more precisely, the totalizer integrates a value over a time period.
The totalizer looks for its source to represent values "per second", "per minute" or "per hour". It is important to select a source time scale that matches the source values. For example, when recording total flow from a meter that is measuring flow rate per second, selecting the "per minute" source time scale is guaranteed to produce results that are incorrect.
You can also use the totalizer to record running time. For this, the source value must be a 1 when the equipment is running and a 0 when stopped. Given a source time scale of "per second" this will add 1 second, per second while the equipment is running and 0 seconds per second while stopped.
An invalid is not taken to mean that the value (or running state) of the tag is 0. If the source's value goes to invalid, it will be assumed that the last known value remains in effect and that value will continue to be used for the integration.
Values are added to the totalizer tag at the end of each elapsed source time scale. This will not necessarily be "on the second" or "on the minute".
A Logger tag should never be attached to the totalizer since this is done for you. At the end of each log interval, values are automatically logged. You have the option of performing a reset of the totalizer tag's value after each write to the log file.
You can cause a reset to be done at times other than the set logging interval, either by providing a reset button for the operator to use, or by configuring a tag to use an external reset. The current value is always logged before a reset is done.
Note: If the totalizer is drawn with a Set Analog Value tag or a Numeric Entry tag, two things will happen when the operator uses either drawing method: the totalizer will log its current value and it will reset to whatever value is set by the drawing method instead of 0.
It should be noted that a plot of the totalizer tag on the Historical Data Viewer will show a constant value from one log interval to the next, with an instant change between values at each log interval.
The current value of the totalizer tag is saved between VTS restarts.
Note: Never attempt to attach a Logger Tag to a Totalizer tag. Totalizer tags have a built in logger.
Also: Note that right-clicking on a counter tag will not cause the Historical Data Viewer window to open.
Totalizer Tag Type Characteristics
Tag Browser Name: Totalizer
Database Table Name: TotalizerTag
Type: Data Logging and Reporting Tags, Calculation
Tag Group Memberships: Analogs, Numeric, Trenders
Log Enabled Variables: Value
Native Drawing Methods: Reset Button, Reset Target, Elapsed Time, Last Logged Value, most Analog Input drawing methods.
Totalizer Tag Type Properties: ID Tab