Add sensor delay upon power on

ESPHome
1

Hello!
Lets say I have a sensor that needs some warmup time after power on before its readings will make any sense. Like MH-Z19 needs about 3 minutes.
Is there a way to add such a delay before sending MQTT messages for such sensor?
Thanks.

2

Hello and welcome, I’m not an MQTT specialist but I’m sure one will be along pretty soon to help you out. Good Luck

3

There is an update interval setting for that component.

Depending on your requirements, the easiest option would be to set

update_interval: 180s

4

Yes this works on power on, but I don’t want that update interval itself to be that long.
I currently managed to add delay by simply hanging the whole ESP for several minutes on every boot

esphome:
  on_boot:
    priority: 200
    then:
      - lambda: |-        
          delay(120000);

But this feels really ugly since the whole controller is unresponsive during this wait time.
I wonder if there are better solutions.

5

A bit late to the party, but I solved this by using the uptime sensor and using an if conditional. It makes for a bit more ugly YAML, but it means the background isn’t suspended.

  on_boot:
    priority: 200
    then:
      - display.page.show: page1
      - component.update: small_display

sensor:
  - platform: uptime
    name: Uptime Sensor
    id: id_uptime

#something something

          - if:
              condition: 
                lambda: 'return id(id_uptime).state > 5;'
              then:
                - logger.log: 
                    format: "Screen 1!"
                    tag: USER
                    level: WARN
                - display.page.show: page1
                - component.update: small_display
1 Like
6

Just wanted to say this (with a much shorter 500mS delay) seems to also have fixed all my unreliable sensor detection on a battery powered ESP8266 device that turned the sensors on/off with a GPIO to save power in deep-sleep. Similar issue, where it took more time for the voltage regulators/capacitors to stabilize enough to reliably be detected by the component initialization than it took for the ESP to boot.

Thanks!

1 Like