Virtual meters

A virtual meter in SmartgridX is a calculated time series. It combines existing measurement points with addition, subtraction, and optional multiplication factors.

What you can calculate

Only combine signals with compatible units and sign conventions. SmartgridX warns when a formula contains mixed units, but it cannot decide whether the result is electrically meaningful.

Create a virtual meter

1. Open Analyses in SmartgridX.
2. Select Compare data and choose the required period.
3. Add the real measurement points you want to inspect to the chart.
4. Under Virtual meters, select Virtual meter.
5. Give the calculated series a descriptive name, such as Combined transformer power.
6. For every source:
   • choose + to add it or - to subtract it;
   • enter a multiplication factor when required;
   • select the measurement point.
7. Check the resulting formula shown above the source list.
8. Select Save as... to retain the analysis for the current account.

The virtual series is drawn as a separate, highlighted line. Select Export CSV to export the plotted real and virtual series together.

Example: two transformer meters

Suppose one site receives power through two transformers and each feeder has its own meter:

Meter transformer A  ──┐
                       ├──  Combined transformer power = A + B
Meter transformer B  ──┘

Use the same power field and unit for both sources. Before using the result, verify the direction of each meter with a known import or export event. A reversed meter can make a correct formula produce an incorrect total.

Example: calculate the unmetered remainder

If a main meter covers an entire switchboard while two branches have their own submeters, the remaining load can be estimated as:

Unmetered remainder = Main meter - Branch meter A - Branch meter B

This result is intended for investigation and reporting. For continuous controller-side calculation, continue with the setup guide.

How time series are combined

Sources do not always report at exactly the same timestamp. SmartgridX aligns the available samples and carries the latest known value forward between samples. The virtual line starts only after every source has delivered at least one value in the selected period.

This has practical consequences:

• a stale or missing source can leave the virtual meter empty or incomplete;
• very different reporting intervals can make short transients look less precise;
• formulas should normally use signals with the same retention period and unit;
• a saved analysis stores the formula, but it does not turn the result into a reusable device elsewhere in the portal.

Analysis or controller configuration?

See Virtual energy meters and meter aggregation for the controller-side options and their safety boundaries.

Troubleshooting