How do I get the TIME for the max_value in a statistic

Configuration
1

I can get the max_value attribute from the statistics of a temperature sensor, but how do I get the time that the actual max_value occurred? I know the times are stored in the database because I can see them in a popup on the chart as I move the cursor over the chart line.

2 Likes
2

Very easy if you want to display the info.
I use the custom mini graph card with the extrema flag.

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type: custom:mini-graph-card
entities:
  - sensor.purpleair_aqi_a
unit: AQI
name: Air Quality (24hr)
icon: none
hour24: true
show:
  fill: true
  legend: false
  labels: false
  name: true
  extrema: true
  average: true
  points: false
  name_adaptive_color: true
  icon_adaptive_color: true
  show_legend: false
font_size: null
line_width: 3
points_per_hour: 4
hours_to_show: 24
color_thresholds_transition: hard
color_thresholds:
  - value: 0
    color: '#68FF43'
  - value: 50.5
    color: '#FFFF55'
  - value: 100.5
    color: '#EF8533'
  - value: 150.5
    color: '#EA3324'
  - value: 200.5
    color: '#8C1A4B'
  - value: 300.5
    color: '#731425'

If you want to pull that data out for use in an automation, then this won’t help.

You could look at min/max or statistics template sensors that might get you closer.

3

Glenn - I’m already using a template to return the max_value; I should have included the configuration :

  - platform: statistics
    name: 'attic_temp_stats'
    entity_id: sensor.h5174_c58b_temp
    sampling_size: 1600
    max_age:
      minutes: 1440

    attic_max:
      friendly_name: 'Attic Max'
      unit_of_measurement: '°F'
      value_template: "{{ state_attr('sensor.attic_temp_stats', 'max_value') | round(0) }}"

I’ve tried variations of as_timestamp, like below, but it doesn’t work:

    time_attic_max:
      friendly_name: 'Time Attic Max'
      value_template: "{{ as_timestamp('sensor.attic_temp_stats', 'max_value') | round(0) }}"
4

Try this in the Template Editor

{{ states.sensor.attic_max.last_changed }}

I’m assuming you left out pasting the - platform: template etc… from your attic_max template sensor as the way it is shown above won’t work.

5

Yes, I left out the platform: template, etc. Like I said, I do get the maximum temperature.

I just tried your suggestion and although it does return a time (in UTC), but for some reason it is the last time the sensor reported a temperature (basically current time), not the time of max_value.

6

It should report:

Time the state changed in the state machine in UTC time

for the template sensor.

Has the sensor reached it’s max value yet, or is it still increasing?

7

Yes, it reached it’s 24-hour maximum about 5 hours ago. Either I’m doing something wrong, or the last_changed is not working against the max_value attribute in the database (the database does have the full 24 hours in it).

8

You have to search the database using an sql query. That’s the only way.

9

Yeah, I guess so. I was really hoping there was an easy way, like your suggestion. What’s weird is that if you click on the sensor you get a popup window that shows the current/last value and a graph of the temperature during the last 24 hours. If you move the mouse cursor over any part of the graph line you get a small popup that shows the temperature and time at that point on the graph.

10

Petro - I didn’t realize that a 2nd Moderator had jumped in when I said “an easy way, like your suggestion”. It was Tom_I that made the first suggestion.

11

Yes, because it did a query and has the data. There’s nothing built into HA that will give you what you want. You’ll have to use the sql integration.

12

Thanks Petro.