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Zigbee devices Smart plugs with energy metering

Shelly S4EM-002CXCEU

EM Gen4. Works with Zigbee2MQTT with no vendor hub or cloud: it pairs with a Zigbee stick and shows up in Home Assistant.

Vendor
Shelly
Model
S4EM-002CXCEU
Type
Smart plugs with energy metering
Power
mains: usually a router that extends the mesh
Firmware updates (OTA)
no

Find it in shops: AliExpress

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What it exposes

FeaturePropertyValuesControl
On / off (1)state_1—settable
Power (2)power_2Wread only
Power (3)power_3Wread only
Voltage (2)voltage_2Vread only
Voltage (3)voltage_3Vread only
AC frequency (2)ac_frequency_2Hzread only
AC frequency (3)ac_frequency_3Hzread only
Current (2)current_2Aread only
Current (3)current_3Aread only
Energy (2)energy_2kWhread only
Energy (3)energy_3kWhread only
Produced energy (2)produced_energy_2kWhread only
Produced energy (3)produced_energy_3kWhread only
Wi-Fi statuswifi_status—read only
IP addressip_address—read only
DHCP enableddhcp_enabled—read only
Wi-Fi Configurationwifi_config—read only
Identifyidentifyidentifysettable

MQTT: state and commands

Zigbee2MQTT publishes the device state to zigbee2mqtt/my_device (my_device is the name you give the device). An example message:

{
  "state_1": "ON",
  "power_2": 12.4,
  "power_3": 12.4,
  "voltage_2": 230,
  "voltage_3": 230,
  "ac_frequency_2": 0,
  "ac_frequency_3": 0,
  "current_2": 0.06,
  "current_3": 0.06,
  "energy_2": 3.21,
  "energy_3": 3.21,
  "produced_energy_2": 0,
  "produced_energy_3": 0,
  "dhcp_enabled": false,
  "linkquality": 120
}

Send commands to zigbee2mqtt/my_device/set:

mosquitto_pub -t zigbee2mqtt/my_device/set -m '{"state_1":"TOGGLE"}'

Watch the topics live from the browser: MQTT client.

Home Assistant automation example

Zigbee2MQTT creates Home Assistant entities from the device name. If it is called my_device, an automation in automations.yaml can look like this:

- alias: "Turn off when idle"
  mode: single
  triggers:
    - trigger: numeric_state
      entity_id: sensor.my_device_power
      below: 2
      for: "00:15:00"
  actions:
    - action: switch.turn_off
      target:
        entity_id: switch.my_device_1

Check the YAML: YAML checker.

How to pair it

  1. In Zigbee2MQTT click Permit join.
  2. Put the device in pairing mode: usually a long press of the reset button (5–10 s) until the LED blinks; bulbs: switch the power off and on 5–6 times.
  3. Keep the device close to the coordinator or a router while pairing.
  4. Give it a clear name: MQTT topics and Home Assistant entities are built from it.

Exact procedure and model notes: the device page in the Zigbee2MQTT docs. No coordinator yet: coordinator picker.

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