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Utility-Meter Calibration

Utility meters decoded by SCM, ERT, and SCMplus protocols report a raw consumption counter, but the RF signal does not carry the counter's unit or scale. Different meters report in different granularities, so the integration cannot derive Energy-dashboard-ready values automatically.

Out of the box, consumption is a plain unitless total_increasing counter. To make it eligible for Home Assistant's Energy dashboard, calibrate the device.

Calibrating a Meter

Open Settings → Devices & Services → rtl_433 → Configure (the gear icon) → Device settings and pick the meter.

Meters whose commodity the integration recognized from the signal are labelled with it in the picker, so you can tell at a glance which devices are calibratable and what they measure. When the meter reports a MeterType or ert_type hint, the commodity is pre-filled from it. You can override it, and re-editing an already-calibrated device shows its stored commodity, unit and scale.

Field Meaning
Commodity none, energy, gas, or water. This sets the sensor's device class. Choosing none clears the calibration and leaves the counter unitless.
Base unit The unit the calibrated counter is expressed in, constrained to the Home Assistant units that are convertible for that commodity.
Scale Multiplier applied to the raw counter so the stored value is in the chosen base unit.

The base unit and scale only appear once you have chosen a real commodity, and the units offered change with it — so the calibration you can build is always one the Energy dashboard will accept.

The Device settings page for the SCMplus gas meter, with the commodity pre-filled to gas and the base-unit and scale controls it reveals

Once calibrated, the consumption sensor gets a real device class, native unit, and state_class: total_increasing. You do not need to pick the display unit in the calibration flow: Home Assistant can convert convertible units in the entity settings.

The counter field itself needs no configuration: SCM and ERT meters report consumption_data and SCMplus meters report Consumption, and both ship in the device library. Neither requires a YAML override.

Statistics Caveat

Changing commodity, base unit, or scale changes the sensor's native unit or device class. Home Assistant treats that as a non-convertible change for long term statistics.

The entity keeps its ID, but previous long-term statistics are orphaned. Calibrate intentionally, ideally once. Saving a calibration reloads the hub so the sensor is rebuilt with the new unit and class.

Model-Scoped Mappings

For models whose unit and scale are authoritatively known, a contributor can ship a model-scoped mapping in the device library so those meters work without per-device calibration.

pyrtl_433 does not include speculative real-meter consumption mappings. A wrong scale would silently corrupt Energy data.