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.

Calibration Flow¶

Open Settings → Devices & Services → rtl_433 → Configure → Device settings. Calibration takes three short steps.

1. 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.

The device picker, with the SCMplus meter labelled "gas detected"

2. Choose the commodity¶

When the meter reports a MeterType or ert_type hint, the commodity is pre-filled from it — for the device you picked, however many meters the hub has. You can override it. Re-editing an already-calibrated device pre-fills its stored commodity, unit and scale.

Choosing none here clears any existing calibration and leaves the counter unitless.

The device settings step for the gas meter, with the meter commodity pre-filled to Gas

3. Set the base unit and scale¶

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

The calibration step for a gas meter, with a base-unit selector and a scale multiplier

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.

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