Time sensor like a stop watch

ESPHome
1

Hi

Seems lika noob question but I have tried to find out how to measure time with ESPHome. I have a pump running on and off and I would like to measure the time its on. I have a relay connected to data pin but how do I get a sensor to report how many seconds it has been on the last minute?

Regards,

Ozcar

2

It would be easier to implement in homeassistant using the history stats sensor:

3

That could work but the time resolution is too low. I need at least second resolution since the pump can start and stop several times per minute. Then of course am using this measured time to calculate other stuff.

4

you could use a couple of global variables to keep track of pump_seconds, and last_pump_time. The second one (last_pump_time) stores the epoch time of when the pump was last turned on.

Then use a binary sensor which indicates when the pump in on or off, and use the on_press automation with a lambda to read epoch time to calculate how many seconds have elapsed and add that to your global variable. Something along these lines anyway.

You could combine this with a 1min interval to figure out how many seconds pump has been on in last minute, and then reset the pump_seconds global.

5

Yes that could work. Epoch time makes it easier to do it. I will try it out.

Still strange that there is no simple way to measure time like with a sensor.

6

I too would like a way for ESPhome to know how long an output has been on so I can use it as a failsafe. Currently I have HA controlling an ESP to control irrigation. A couple of times I have not realised that I restarted HA while the irrigation was on. This caused HA to essentially reset the irrigation script and then not send a stop command to the ESP… leaving the sprinklers on far longer than they should have been before I noticed what had happened. If there is a way to have an in-built timer I could include a failsafe to turn off the ESP output after say 1 hr.

I’m wondering if this can be done with the ESPhome automations, something like:

on_press:
  - then:
      - delay: '01:00:00'
      - switch.turn_off: output_whatever
7

I would also like something similar for my irrigation setup. And also on top a failsafe if for whatever reason it loses wifi or api connection for more than e.g. 5mins so can auto-stop watering, otherwise will never receive the off command from HA.

I never thought of a delay option, because that seems much easier than my thinking. Should be possible like you mention

Found this on the documentation of esphome

on_...:
  then:
    - switch.turn_on: relay_1
    - delay: 2s
    - switch.turn_off: relay_1
    # Templated, waits for 1s (1000ms) only if a reed switch is active
    - delay: !lambda "if (id(reed_switch).state) return 1000; else return 0;"
8

This is how I’ve implemented a fail-safe. When it switches on, a script is started that will delay for whatever time you like and then switch off. If it is switched off before the script finishes, the script is stopped.

switch:
  - platform: gpio
    id: device_relay_1
    name: ${entity_prefix_1}
    pin: 
      number: GPIO12
    on_turn_off:
      - script.stop: timer_script_1
    on_turn_on:
      - script.stop: timer_script_1
      - script.execute: timer_script_1

script:
  - id: timer_script_1
    then:
      - delay: 15 min
      - switch.turn_off: device_relay_1
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