Support default value in sensor group helper if device unavailable when combining multiple sensors

Feature Requests
1

Feature Request

This request is for Sensor Group Helper entities.

When combining multiple sensors it is not possible to define a default value when a device becomes unknown or unavailable.

By supporting a default value in such a case, automations can be a little more flexible.

What happens currently?

If you combine all battery levels (%) and set to Min, then when an entity becomes unavailable it is not considered at all.

In other words, the battery level is 100% when a device becomes unavailable. However, in reality the device may be dead (0%).

Use case

I have lots of battery powered devices. I like to get low battery alerts via automation. I combine multiple battery level (%) sensors into a single “minimum battery level” so that I can alert.

I like using the helper device because I don’t want to know about all batteries; just a specific set.

Workaround

A current workaround is to use a template, instead of a combination of sensors.

The following template is equivalent to “min” and a default value of 0% when a device is dead (unavailable).

  • Template Sensor
  • Unit of measurement: %
  • Device class: Battery
  • State class: Measurement
  • “Min” measurement template source:
{%
  set battery_levels = [
    states('sensor.h5100_1f7c_battery') | float(0),
    states('sensor.h5100_635f_battery') | float(0),
    states('sensor.h5100_4a0b_battery') | float(0),
    states('sensor.water_sensor_7_pro_battery_level') | float(0),
    states('sensor.water_sensor_7_pro_battery_level_2') | float(0),
    states('sensor.front_door_lock_battery_level') | float(0),
    states('sensor.c20_row_battery_level') | float(0)
  ] | sort
%}{{
  battery_levels[0]
}}

If a device becomes unavailable (e.g. battery dies), then the sensor measurement will be 0%.

Software version of report

Core 2025.5.3

2

FYI

{{ [ 'sensor.h5100_1f7c_battery',
     'sensor.h5100_635f_battery',
     'sensor.h5100_4a0b_battery',
     'sensor.water_sensor_7_pro_battery_level',
     'sensor.water_sensor_7_pro_battery_level_2',
     'sensor.front_door_lock_battery_level',
     'sensor.c20_row_battery_level' ] | map('states') | map('float', 0) | min }}
1 Like
3

Thank you and Nice! I tried using map and was floundering. I like this workaround better.

I updated my sensors to match.