In the parameters of a sensors we can select a unit of measurement, but if we want no unit of measurement this is not possible.
It would be great if we could add the none choice to this list.
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Can you give an example of a sensor that you can’t model please?
(e.g. number of loaves in the cupboard, the value of a mode setting?)
According to the dev docs, the default sensor device class is None which gives a genric sensor, or for Number. The State classes docs are more explicit:
A sensor is a read-only entity that provides some information. Information has a value and optionally, a unit of measurement.
The Python code seems to default to None if a different value is not set.
Is this an issue creating a new Sensor / Number / Entity via a particular GUI / integration / API not accepting None perhaps?
I’ve not tested it but could see issues where an existing Add-On defines a sensor with a device class (native_unit_of_measurement), and you want to change it to None as there might not be code to do a conversion?
In fact these are temperature sensors that display the temperature in degrees Celsius, so far nothing abnormal.
But since I integrate it into a state-label of a picture-elements type map, I would like not to display the unit of measurement.
Here are 2 pictures showing the result I obtained by creating a new sensor without a unit of measurement.
So what you asking for is the ability to change the GUI presentation of specifically a temperature sensor, and not the generic sensor entity (which is already explicitly supported - links to the source code above).
HASS has additional code for SensorDeviceClass.TEMPERATURE to use system / localisation setting for temperature units so it understands what temperature is, so only offers temperature unit options - e.g.:
A workaround is to create a template function based on the sensor, e.g.:
{{ states('sensor.study_pir_air_temperature', rounded=True, with_unit=True) }}
Gives: 22.6 °C
{{ states('sensor.study_pir_air_temperature', rounded=True, with_unit=False) }}
Gives: 22.6
{{ states('sensor.study_pir_air_temperature', rounded=True, with_unit=False) | float }}
Gives: 22.6
This method allows you to create whatever formatting you wish for.
Thanks for the reply,
Indeed we can get around the problem in different ways, but I found it interesting to have this option directly in the graphical interface of all sensors.
Another work around that more accurately meets your needs is to use the custom button-card to display the state of an entity in the name field, where you can modify the state text with JavaScript. Here’s a simple example that adds the “degrees” symbol to the value of a temperature in a picture-elements card:
type: picture-elements
elements:
- type: custom:button-card
style:
top: 35%
left: 30%
entity: sensor.out_temperature_ha
color_type: card
color: rgba(0, 0, 0 ,0)
name: |
[[[
return states['sensor.out_temperature_ha'].state + "°";
]]]
show_icon: false
styles:
card:
- '--ha-card-border-width': 0px
name:
- font-size: 90px
tap_action:
action: more-info
The style sets the placement of the text. color rgba(0,0,0,0) makes the button transparent, and setting the border width to 0px leaves a button with only the text. Obviously not the best option, but visually it works great. If you don’t want any tap action, just set the action to none.