Soil moisture showing the same voltage 24/7

ESPHome
1

i have an esp 32 with a voltage soil moisture sensor and it always reports the same voltage… here is my yaml.

esphome:
  name: multi
  friendly_name: multi

esp32:
  board: esp32dev
  framework:
    type: arduino
    version: latest
# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "xxxxxxxxxxxxxxxxxxx"
mdns:
  disabled: false

ota:
  - platform: esphome
    password: "xxxxxxxxx"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password
  manual_ip:
    static_ip: 192.168.1.188
    gateway: 192.168.1.254
    subnet: 255.255.255.0
  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Multi Fallback Hotspot"
    password: "xxxxxxxxx"

captive_portal:

sensor:
  - platform: dht
    pin: GPIO4
    model: DHT22
    temperature:
      name: "multisensor Temperature"
    humidity:
      name: "multisensor Humidity"
    update_interval: 60s
  - platform: wifi_signal
    name: 'WiFi Signal'
    entity_category: diagnostic
  - platform: uptime
    name: 'Uptime'
    entity_category: diagnostic
    unit_of_measurement: s


  - platform: adc
    pin: GPIO33
    id: esp_wassernapf_volt
    name: "soil Volt"
    update_interval: 900s
    accuracy_decimals: 5    
    unit_of_measurement: 'V'
  

  - platform: template
    name: "soil volume"
    id: water1
    unit_of_measurement: "gal"
    

    filters:
      - calibrate_linear:
          # 0.1v = 0ml
          # 1v = 1700ml
          - 0.06 -> 0.0 # empty
          - 0.1 -> 1.0 # half full  or 10 mL of water
          - 0.2 -> 2.0 # 20 ml -- full will be when the entire pad is covered  
    icon: "mdi:water-percent"
    update_interval: 1s
    accuracy_decimals: 1
    lambda: |-
      return id(esp_water_volt).state;   

web_server:
  port: 80





text_sensor:
  - platform: version
    name: 'ESPHome Version'
    entity_category: diagnostic
  - platform: wifi_info
    ip_address:
      name: WiFi IP Address
      entity_category: diagnostic
    ssid:
      name: WiFi SSID
      entity_category: diagnostic
    mac_address:
      name: WiFi MAC Address
      entity_category: diagnostic
    dns_address:
      name: WiFi DNS Address
      entity_category: diagnostic
2

You have better luck here, if you post your sensor and wiring as well.
And your log.

3

What voltage does your moisture sensor output?

With this config you are limited to a maximum of 0.95V:

See the attenuation setting if you need a wider input voltage range: Analog To Digital Sensor — ESPHome

4

it shows 1.039

5

Then you need to set the ADC attenuation option.

6

the sensor looks just like this sensor.

the sensor is wired directly to the esp32.
here are the logs for the espboard https://pastecode.io/s/ius217px

my full yaml https://pastecode.io/s/y1ib8r8v

7 
  - platform: adc
    pin: GPIO33
    id: esp_wassernapf_volt
    name: "soil Volt"
    update_interval: 900s
    attenuation: auto ### <----- ADD THIS
    accuracy_decimals: 5    
    unit_of_measurement: 'V'

This will allow you to measure ~0.075V to ~3.12V.

If your sensor puts out more than 3V you will need a physical voltage divider. Or better yet an external I2C ADC that is actually linear (the ESP one is awful at the extreme ends of its range).

8

well that seemed to do the trick its showing a voltage of 2.46 so im guessing if i add water to that pot it should go up, or if i look tomorrow it should go down.

9

That’s water level sensor, I doubt you get good results for soil moisture…

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