Pre-order €49 until 9 Nov, then €5911 days left at this priceships on 10 November 2026Pre-order →
EN
EnglishFrançaisDeutsch
Dashboard Pre-order€49

Home / WeCo battery in Home Assistant

WeCo battery in Home Assistant

Each module of the cluster, locally, without a cloud in between.

  • About 1 minute
  • Zero YAML
  • No HACS, no ESPHome
  • 100 % local
Plug & play

From the box to Home Assistant in about a minute

This is the whole procedure, really. Watch it play, then read the details below if you like details.

  1. 0:00On the box: three fields

    Open the box’s page from your phone and type the address of Home Assistant, a user and its password. The port and the discovery are already set.

    MQTT & Home Assistant

    ✓Home Assistant discovery (sensors created automatically)

    SaveStatus: connected

  2. 0:20In Home Assistant: nothing to do

    The WeCo Monitor device appears on its own under MQTT, with every sensor named and with its unit. No YAML, no add-on to code, no restart.

    Settings › Devices & services › MQTT

    WeCo MonitorMoniWatt · MoniWatt for WeCo
    New
    • SOCsensor.weco_monitor_soc78 %
    • Powersensor.weco_monitor_power+1 450 W
    • Module 1 SOCsensor.weco_monitor_module_1_soc78 %
    • Cell minsensor.weco_monitor_cell_min3.309 V
    • Temperaturesensor.weco_monitor_temperature24.5 °C
    • Sohsensor.weco_monitor_soh98 %
  3. 1:00Your dashboard, already live

    Drop the sensors on a dashboard, add them to the Energy page, build automations. They refresh on their own.

Illustration with simulated values. The labels on the box are the real ones; Home Assistant shows the sensor names in English.

Setup

Enter your MQTT broker in the box settings. Home Assistant discovers WeCo Monitor and creates its sensors; nothing to write by hand.

Sensors

  • sensor.weco_monitor_soc
  • sensor.weco_monitor_power, …_voltage, …_current
  • sensor.weco_monitor_module_1_soc, …_module_2_soc … one set per module
  • sensor.weco_monitor_cell_min, …_cell_max, …_cell_delta
  • sensor.weco_monitor_temperature
  • sensor.weco_monitor_soh
  • binary_sensor.weco_monitor_alarm

Automations

  • A notification when one module ends the evening more than 5 points below the others.
  • Start the water heater when the cluster is above 95% and still charging.
  • Send yourself the state of health once a month.

JSON

GET http://moniwatt.local/api.json?key=YOUR_KEY

{"soc": 74, "power": 2150, "voltage": 53.0, "current": 40.6,
 "modules": [{"soc": 75, "cell_min": 3.331, "cell_max": 3.339},
             {"soc": 73, "cell_min": 3.328, "cell_max": 3.337}],
 "temp": 22.5, "soh": 99, "alarms": []}
Home Assistant automations

Your appliances run on the sun, by themselves

WeCo Monitor tells Home Assistant when the battery fills up and when it runs low. Four simple rules, and the washing machine, the water heater and the car use your sun instead of the grid. Watch a day:

10:00

Your solar production

Your consumption

OverviewLive

Automations

  • Washing machine on the sun
  • The car follows the sun
  • Hot water for free
  • Gentle evening heating

Logbook

    • Solar production
    • House and heating
    • Washing machine
    • Water heater
    • Electric car
    • Battery level
    • From the grid
    • Sold to the grid for little
    Solar used at home0 %
    Bought from the grid0
    Self-sufficiency0 %
    Saved on this day0vs. the same day without automation
    Over a year0if 150 days look like this one
    Create these automations in 2 minutes →

    Simulation of a sunny day for a house with 5 kWp of panels, a 10 kWh battery, a car that needs 10 kWh and a water heater. The energy delivered to each appliance is the same in both scenarios; only the timing changes. Your figures depend on your system, your tariff and the weather.

    No code

    Your first automation in 30 seconds

    In Home Assistant, Settings › Automations › Create: pick the sensor, the threshold and what should happen. Everything with the mouse.

    Prefer YAML? The same automation
    alias: Battery low
triggers:
  - trigger: numeric_state
    entity_id: sensor.weco_monitor_soc
    below: 20
actions:
  - action: notify.notify
    data:
      message: "Battery at {{ states('sensor.weco_monitor_soc') }} %"
    Automation generator

    Build your automation, copy, paste

    Pick what to watch, set the threshold and what should happen: the YAML is written for you with the real WeCo Monitor sensor names. Nothing is sent anywhere, it all happens in your browser.

    What to watch

    Threshold

    Then

    automation.yaml

    In Home Assistant: Settings › Automations & scenes › Create automation › ⋮ › Edit in YAML, paste, Save.

    Is it really that simple?

    Do I need HACS, ESPHome or a custom integration?

    No. The box talks MQTT, which Home Assistant understands natively, and announces its own sensors (MQTT discovery). Nothing to install on the box, nothing to code.

    I don’t have an MQTT broker yet. Is that a problem?

    No: in Home Assistant, Settings › Add-ons › Mosquitto broker › Install, then Start. Home Assistant then offers to configure MQTT: one click. Two minutes, once, and it serves every MQTT device you will ever add.

    Do I need the internet or the Cloud for Home Assistant?

    No. Everything stays on your home network: the box speaks directly to Home Assistant. The free Cloud is a separate option, for seeing your system from anywhere.

    Can I use Home Assistant and the Cloud at the same time?

    Yes. Screen, local dashboard, Home Assistant and Cloud all work together, and none of them changes anything on your battery.

    Keep reading

    ◎Features→▤Specifications→⚙Installation→☁Cloud→⏱Runtime calculator→✎Guides→

    Every WeCo module, in one view

    Pre-order now. The box is tested on WeCo modules before it ships on 10 November 2026.

    Plug & play: working in about a minute

    Pre-order for €49Pre-order price · €59 from 10 Nov · ships on 10 November 2026 · free cancellation until dispatch