Absolute sensor readings, thresholds & changes in readings

Why is it difficult to deal with absolute sensor readings, as opposed to readings crossing a threshold in HA? Triggering an action because you are below a threshold (absolute reading) rather than crossing the actual threshold seems excessively complicated. I’m sure there are plenty of good reasons, but …

A similar question really about HA only responding to changes.


(head covered for all the incoming flak :))

It’s not difficult. You just haven’t been shown how to do it. One trigger and one condition. For example to execute actions on any sensor value below 42:

  - platform: state
    entity_id: sensor.foo
    to: # null "to" triggers on *all* state changes, ignores attribute changes
  - condition: numeric_state # only do the action if the state value is below 100
    entity_id: sensor.foo
    below: 42