ESPHome emontx component - sensors missing

FredM67 · 13 June 2026 12:54

Sure, we can add a note in the doc.

FredM67 · 13 June 2026 12:55

On reboot, the component starts exactly as before, as far as I know

awjlogan · 13 June 2026 13:36

Do we know why @glyn.hudson ‘s sensors were disabled after a restart?

glyn.hudson · 15 June 2026 14:49

Interesting, I’ve still not able to restore the sensor entries for me emonTx6. I’ve tried everything I can think of. The ESPHome still looks like this:

The emonTx6 WiFi module is working fine, I’m able to connect to it and see it posting data and reflash the ESP via OTA.

borpin · 16 June 2026 09:34

The question is why is this error being generated.

github.com/esphome/esphome

esphome/components/emontx/emontx.cpp

d8fa0e414


      
          */
          void EmonTx::dump_config() {
           ESP_LOGCONFIG(TAG, "EmonTx:");
          
          #ifdef USE_SENSOR
           ESP_LOGCONFIG(TAG, "  Registered sensors: %zu", this->sensors_.size());
           for (const auto &sensor_pair : this->sensors_) {
             ESP_LOGCONFIG(TAG, "    Sensor: %s", sensor_pair.first);
           }
          #else
           ESP_LOGCONFIG(TAG, "  Sensor support: DISABLED");
          #endif
          }
          
          /**
          * @brief Sends a command string to the emonTx device via UART.
          *
          * @param command The command string to send (LF will be appended automatically).
          */
          void EmonTx::send_command(const std::string &command) {
           ESP_LOGD(TAG, "Sending command to emonTx: %s", command.c_str());

FredM67 · 16 June 2026 11:50

Is defined as soon as at least one sensor is defined in the yaml.

Anyway, I’ll make a double check..

awjlogan · 16 June 2026 21:17

@glyn.hudson - I guess the full YAML would be helpful to look at in this case?

glyn.hudson · 17 June 2026 10:02

esphome:
  name: emontx6
  friendly_name: emonTx6

esp32:
  board: esp32-c3-devkitm-1
  framework:
    type: esp-idf

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "xxxxxxxxxxxxxxxxxxxxxx"
  homeassistant_services: true
  custom_services: true

ota:
  - platform: esphome
    password: "xxxxxxxxxxxxxxxxxxxxxxx"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Emontx6 Fallback Hotspot"
    password: "xxxxxxxxxxxxxxxxxx"

captive_portal:

# External component for the HA bridge
# (emontx itself is now built into ESPHome)
external_components:
  - source:
      type: git
      url: https://github.com/FredM67/esphome
      ref: emontx-ha-bridge
    components: [emontx_ha_bridge]
    refresh: 0s

emontx_ha_bridge:

uart:
  id: emontx_uart
  rx_pin: GPIO20
  tx_pin: GPIO21
  baud_rate: 115200
  rx_buffer_size: 2048

#emontx:

substitutions:
  emoncms_server: "https://emoncms.org"
  emoncms_node: "emontx"
  emoncms_apikey: "xxxxxxxxxxxxxxxxxxx"

http_request:
  useragent: esphome/emontx
  timeout: 10s

emontx:
  on_json:
    - then:
        - http_request.post:
            url: !lambda 'return "${emoncms_server}/input/post";'
            request_headers:
              Content-Type: "application/x-www-form-urlencoded"
            body: !lambda |-
              return "node=${emoncms_node}&apikey=${emoncms_apikey}&fulljson=" + raw_json;

borpin · 17 June 2026 12:39

You don’t have any sensors defined?

FredM67 · 18 June 2026 05:38

glyn.hudson:

esphome:
  name: emontx6
  friendly_name: emonTx6

esp32:
  board: esp32-c3-devkitm-1
  framework:
    type: esp-idf

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "xxxxxxxxxxxxxxxxxxxxxx"
  homeassistant_services: true
  custom_services: true

ota:
  - platform: esphome
    password: "xxxxxxxxxxxxxxxxxxxxxxx"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Emontx6 Fallback Hotspot"
    password: "xxxxxxxxxxxxxxxxxx"

captive_portal:

# External component for the HA bridge
# (emontx itself is now built into ESPHome)
external_components:
  - source:
      type: git
      url: https://github.com/FredM67/esphome
      ref: emontx-ha-bridge
    components: [emontx_ha_bridge]
    refresh: 0s

emontx_ha_bridge:

uart:
  id: emontx_uart
  rx_pin: GPIO20
  tx_pin: GPIO21
  baud_rate: 115200
  rx_buffer_size: 2048

#emontx:

substitutions:
  emoncms_server: "https://emoncms.org"
  emoncms_node: "emontx"
  emoncms_apikey: "xxxxxxxxxxxxxxxxxxx"

http_request:
  useragent: esphome/emontx
  timeout: 10s

emontx:
  on_json:
    - then:
        - http_request.post:
            url: !lambda 'return "${emoncms_server}/input/post";'
            request_headers:
              Content-Type: "application/x-www-form-urlencoded"
            body: !lambda |-
              return "node=${emoncms_node}&apikey=${emoncms_apikey}&fulljson=" + raw_json;

Your yaml does not define any sensor, that’s why you don’t see anything in HA and/or in the log.

glyn.hudson · 30 June 2026 18:34

Oh dear, I’ve no idea how the sensor section has disappeared. I’ve now added it back

sensor:
  - platform: emontx
    tag_name: "V1"  # Use "V1"-"V3" for multi-phase; see Sensor Indexing for "Vrms" (single-phase)
    name: "Voltage"
  - platform: emontx
    tag_name: "P1"
    name: "Power CT1"
  - platform: emontx
    tag_name: "E1"
    name: "Energy CT1"

It’s working again now! Very sorry for all this hassle
Thanks a lot for your help.

borpin · 30 June 2026 20:02

GIGO