Finding max value from an MQTT sensor

Configuration
1

Hi,

How would I create a template sensor that shows the maximum value from an MQTT sensor?

I’ve tried the following, but see an error relating to a python dict item not being available:

sensor:

  • platform: mqtt
    state_topic: “/house/nursery/temp”
    unit_of_measurement: “C”
    name: “Nursery temperature”
  • platform: template
    sensors:
    max_nursery_temperature:
    friendly_name: “Maximum temperature”
    value_template: {{ max(states.nursery_temperature) }}
    unit_of_measurement: “C”
2

I use some sensor templates…

- platform: template
  sensors:
      greenmaxtemp:
          friendly_name: 'greenhouse max temp'
          value_template: >
              {% set greencurrenttemp1 = (states.sensor.gh_sensor_temp.state | float) %}
              {% set greencurrent_threshold_max = (states.input_slider.green_max_temp.state | float) %}
              {% macro max(X, Y) -%} {{X|float if X|float > Y|float else Y|float }} {%- endmacro %}
              {{ max(greencurrent_threshold_max, greencurrenttemp1) }}

- platform: template
  sensors:
      greenmintemp:
          friendly_name: 'greenhouse min temp'
          value_template: >
              {% set greencurrenttemp2 = (states.sensor.gh_sensor_temp.state | float)%}
              {% set greencurrent_threshold_min = (states.input_slider.green_min_temp.state | float) %}
              {% macro min(X, Y) -%} {{X|float if X|float < Y|float else Y|float }} {%- endmacro %}
              {{ min(greencurrent_threshold_min, greencurrenttemp2) }}

And some input sliders…

green_max_temp:
  name: Greenhouse Max Temp
  initial: -40
  min: -40
  max: 50
  step: 0.01
green_min_temp:
  name: Greenhouse Min Temp
  initial: 50
  min: -40
  max: 50
  step: 0.01
3

Thanks Keith,

Am I right in saying that yours compares two different values to find which is the highest and which of a pair is the smallest?

I’m trying to look through the history of all values from my nursery sensor and then display this.

Matt

4

Have you looked at …

or

5

Mine stores the lowest and highest values in the input sliders and compares against the read ones from the sensors. I store the values to disc so that they permanent immediately after they have changed.

6

Thank you. I’ve tried the statistics sensor, but it doesn’t seem to read data from the history.

I’ll try the history statistics sensor to see how I get on with that. I’d then like to reference the maximum value only so that I can get this returned by an Alexa skill.

Matt