Create a sensor from and entity attribute

Configuration
1

Hi all,

I hope this is the right category in this forum to poste my question, else please move this subject to the related category.

My question:
I have one thermometer (from Tuya) that is not really working with home Assistant, but instead of reading the current temperature I can see some corresponding values.

Let me give more detail:

The device entity id is: climate.thermostat
The attribute where I see values is named: current_temperature

But as explained in “current_temperature” I see only value like 3.8 which give 19°C (on the device screen), 3.9 gives 19.5 etc…

What I want to do is create an new entity or senssor from the the above attribute and make a table of correspondance like this:

3.8 ->19 °C
3.9 → 19.5 °C
4 → 20 °C
4.1 → 20.5 °C
4.2 → 21 °C
4.3 → 21.5 °C
4.4 → 22 °C
4.5 → 22.5 °C
4.6 → 23 °C
4.7 → 23.5 °C
etc…

By doing this I can use this new sensor / entity to get the real value of the temperature as I can read it on the screen of the physical device.

I hope my issue is clear for you, else please tell me and I’ll give you more details.

Many thank for all your support.
Phil

2
3

Thank you for your quick reply, based on your answer I have trid this, but I get an error message

compensation:
  Room_temperature_wall_mounted:
    source: climate.thermostat
    attribute: current_temperature
    unit_of_measurement: °C
    data_points:
      - [3.8, 19]
      - [3.9, 19.5]
      - [4.0, 20]
      - [4.1, 20.5]

Error message:
Invalid config for [compensation]: [Room_temperature_wall_mounted] is an invalid option for [compensation]. Check: compensation->compensation->Room_temperature_wall_mounted. (See /config/configuration.yaml, line 100).

THank you for your support

4

You need to get rid of the capital R in the object id.

5

THanks the correction is done. Now just for my understanding, is this supposed to creat an entity named: room_temperature_wall_mounted, where the converted values will be stored ? if this is the case I can’t see this in the “STATUS” tab ?

Maybe this might help you, I have a separate “sensor” file

Many thanks for your support.

6

I would probably have used a template sensor instead. Not because it’s better but it would have saved you a lot of manual typing.

sensor:
  - platform: template
    sensors:
      room_temperature_wall_mounted:
        value_template: "{{ state_attr('climate.thermostat', 'current_temperature') | float * 5 }}"
        unit_of_measurement: °C

because 19/3.8 = 5, 19.5/3.9 = 5 and 20.5/4.1 = 5. So there is no reason to create a compensation table in my opinion.
But now that it’s done it won’t make any difference, unless you believe it will go above or below your current range.

What is the

?

7

Thank you for your answer. Making a template sensor was my first idea and your code seems to be what I wanted to do. Just one question, where and how to enter the conversion value into the code you have given above ?

The “status” tab is as shown below

image
image1664×302 14.1 KB

8

Umm… it is there. All you need to do is copy it to your configuration and reload template entities.
When that is done it should be visible in states tab

9

Sorry I didn’t see the float 5 so it’s clear for me. Many thanks I’ll try this and come back to let you know.

10

Thank you very much, it’s working perfectly.