2026.2.3
Home ▸ Integrations ▸

IoTaWatt

Integration for the IoTaWatt Open WiFi Electricity Monitor. It will collect data from the Current Transformer Clamps (Input CTs) and any Outputs that are defined on the IoTaWatt and create them as sensors in Home Assistant.

Configuration

To add the IoTaWatt device to your Home Assistant instance, use this My button:

Manual configuration steps

If the above My button doesn’t work, you can also perform the following steps manually:

  • Browse to your Home Assistant instance.

  • Go to Settings > Devices & services.

  • In the bottom right corner, select the Add Integration button.

  • From the list, select IoTaWatt.

  • Follow the instructions on screen to complete the setup.

Energy management and sensor availability

You can use the energy sensors directly with the Home Assistant energy dashboard.

IoTaWatt Inputs are available as sensors and are shown on the IoTaWatt device page in Home Assistant.

Any Outputs you create within the IoTaWatt unit are also available as sensors for use in the energy dashboard and templates. However, they are not listed on the IoTaWatt device page because of the Home Assistant policy on unique naming. When you configure the energy dashboard or create a template or helper, start typing the name of a defined IoTaWatt output. Home Assistant suggests completing the sensor name.

Energy production systems

If you have an energy production system such as solar panels, follow these instructions:

Configure IoTaWatt

You will need to configure IoTaWatt output sensors for consumption, export, and production.

For example:

Name Unit Formula
MainsConsumption Watts (Main_In_Red + Main_In_White + Main_In_Blue) max 0
MainsExport Watts ((Main_In_Red + Main_In_White + Main_In_Blue) min 0) abs
Solar Watts ((Solar_Red max 0) + (Solar_White max 0) + (Solar_Blue max 0))

Replace (Main_In_Red + Main_In_White + Main_In_Blue) with the correct formula for your main feed.

Using a solar net system

The IoTaWatt team recommends that the inputs for solar reads positive which can be achieved by either changing the orientation of the CT sensor or in the IoTaWatt’s input settings, check Reverse.

Replace (Main_In_Red + Main_In_White + Main_In_Blue) with (Main_In_Red + Main_In_White + Main_In_Blue - Solar)

If you have two solar sensors named Solar1 and Solar2 you would use: (Main_In_Red + Main_In_White + Main_In_Blue - Solar1 - Solar2)

Configure Energy Management

The IoTaWatt Outputs are available for use:

In the Grid Consumption settings, select MainsConsumption.wh
In the Return to grid settings, select MainsExport.wh
In the Solar production settings, select Solar.wh