Outputs the first value within a given sampling interval.

For example, if a sensor gives raw data every 5 minutes, but an hourly sampling interval is applied to a chart, Open() will give the first raw data point reported over the previous hour.

Specifically, the Open() reported value at 2:00, is the raw data point at 1:05 if a five minute interval is used.



Sensor ID

The unique ID of the sensor data to be used in the function.


This function must be run directly on raw sensor data. An internal function cannot be used (e.g. High(Previous(4))), as this does not pass all the required information.

Example Usage as an Expression:

Open('PRV1-2B.PRV Flow Rate'): Find open values from sensor PRV1-2B. PRV Flow Rate

Examples Reference Chart:

The following example shows various reports of daily tank levels overlaid on an Candlestick Chart. The Open and Close value indicate whether the tank experienced a net filling or draining through the day, while High and Low show the range of values that day. The Average value shows the central tendency.

For information on setting up custom equations and syntax, please refer to Analytical Functions.