Problem with template and attributes

Hello everyone. I wanted to ‘extract’ an attribute from a switch and use it as separate device.
I searched a bit in the forum but I am not sure what is wrong here:

sensor:
    platform: template
    sensors:
        solar_erzeugt:
          value_template: '{{ states.switch.solaranlage.attributes.current_power_w }}'
          unit_of_measurement: 'kWh'

That is the entry of my template configuration.yaml

Thank you for your help

Best regards,
Sebastian

Have you tested your template in the dev-tools?

I use the following template for that. With “state_attr” you don’t get an error when the enity isn’t available.

{{ state_attr('switch.solaranlage', 'current_power_w') | float }}

Never usedthe dev tools. I am new with home assistant. Where can I finde them?

Develpoer tools in the left menu and then template tab. Just paste your template code there and check if you have the correct result.

A sorry. Was in germa mode. Have changed it now. Much easier with documentation and so on. :slight_smile:

Works in the dev tools and also the sensor is there.

Tank you