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CSE7761 Power Sensor

The cse7761 sensor platform allows you to use your CSE7761 voltage/current and power sensors with ESPHome. This sensor is commonly found in Sonoff Dual R3 v1.x.

NOTE

SAFETY HAZARD: Some devices such as Sonoff POWs/Shelly/etc, have the digital GND connected directly to mains voltage so the GPIOs become LIVE during normal operation. Our advice is to mark these boards to prevent any use of the dangerous digital pins.

As the communication with the CSE7761 done using UART, you need to have an UART bus in your configuration with the tx_pin and rx_pin connected to the CSE7761. Additionally, you need to set the baud rate to 38400 and parity to EVEN.

# Example configuration entry
sensor:
  - platform: cse7761
    voltage:
      name: 'CSE7761 Voltage'
    current_1:
      name: 'CSE7761 Current 1'
    current_2:
      name: 'CSE7761 Current 2'
    active_power_1:
      name: 'CSE7761 Active Power 1'
    active_power_2:
      name: 'CSE7761 Active Power 2'

NOTE

The configuration above should work for Sonoff Dual R3 v1.x.

Configuration variables

Section titled “Configuration variables”

  • voltage (Optional): Use the voltage value of the sensor in V (RMS). All options from Sensor.

  • current_1 (Optional): Use the current value of the channel 1 in amperes. All options from Sensor.

  • current_2 (Optional): Use the current value of the channel 2 in amperes. All options from Sensor.

  • active_power_1 (Optional): Use the (active) power value of the channel 1 in watts. All options from Sensor.

  • active_power_2 (Optional): Use the (active) power value of the channel 2 in watts. All options from Sensor.

  • update_interval (Optional, Time): The interval to check the sensor. Defaults to 60s.

  • uart_id (Optional, ID): Manually specify the ID of the UART Component if you want to use multiple UART buses.

Power Direction

Section titled “Power Direction”

Active power is signed, so it shows which way power flows: a load reads positive and power fed back, for example from a solar inverter, reads negative. On the Sonoff Dual R3 v1.x the board wires the current into the chip the other way round, so normal loads read as negative watts. Flip the sign with a filter on each power sensor:

sensor:
  - platform: cse7761
    active_power_1:
      name: 'CSE7761 Active Power 1'
      filters:
        - multiply: -1
    active_power_2:
      name: 'CSE7761 Active Power 2'
      filters:
        - multiply: -1

If a channel only ever powers loads, - lambda: return fabsf(x); also works, but it hides the direction. On a board with a clip-on current transformer, such as the Sonoff POW CT, turn the clamp around instead.

See Also

Section titled “See Also”