Derived Signals can be created to calculate values based on a combination of values from other signals. This is only supported if using OFOSC connection, it is not available while using restAPI connection.
For example, you could clean a messy signal by ignoring negative values, or convert a signal that reports Hydraulic Grade to Pressure by subtracting the elevation and multiplying by the appropriate conversion factor. A common use of Derived Signals is to convert the tank level to HGL (by summing the base elevation of the tank to the level) so it can be used by WaterSight to automatically adjust levels in the tanks for the all period of the simulation run.
To create a derived signal, see instructions here - Adding and Updating Sensors and Smart Meters
Adding and Updating Sensors and Smart Meters
Sensor Data Acquisition Requirements