Zigbee P1 Meter

Custom firmware for the Homey Energy Dongle (ESP32-C6) that reads DSMR 5.0 telegrams from a smart meter P1 port and exposes 3-phase electrical data over Zigbee.

Probably also works for other similar hardware.

Should work with any DSMR 5.0 compliant meter (Landis+Gyr, Kaifa, Kamstrup, Iskra, Sagemcom, etc).

Was written for my use case where I had a Homey Energy Dongle but wanted to utilize the Zigbee capability of the C6 instead of wifi. Can probably be improved a bunch and/or support more devices, feel free to write a PR.

Here is an example of how you can use the data in a dashboard

Flashing the Firmware

Pre-built firmware is available on the Releases page

Entering Flash Mode

The dongle has no dedicated boot button. To enter flash mode:

1. Unplug the dongle from USB
2. Insert a paperclip into the pinhole reset button and hold it down
3. Plug in the USB-C cable while still holding the button
4. Release after ~1 second

Flash via Web Browser (easiest)

1. Download zigbee_p1_meter.bin from the latest release
2. Open the ESP Web Flasher
3. Put the dongle in flash mode (see above)
4. Click Connect, select the serial port, and set the flash address to 0x0
5. Choose the .bin file and click Program

Flash via command line

Install esptool (pip install esptool) and download zigbee_p1_meter.bin from the latest release.

Windows:

esptool.py --chip esp32c6 --port COM3 --baud 460800 write_flash 0x0 zigbee_p1_meter.bin

Find your port in Device Manager under Ports (COM & LPT).

macOS / Linux:

esptool.py --chip esp32c6 --port /dev/ttyACM0 --baud 460800 write_flash 0x0 zigbee_p1_meter.bin

Find your port with ls /dev/cu.usb* (macOS) or ls /dev/ttyACM* (Linux).

Z2M Setup

Add a new external converter to Z2M, either through the UI or in the file system like described below

1. Copy z2m/homey_p1_meter.mjs to your Z2M data/external_converters directory
2. Add to configuration.yaml:

   external_converters:
     - homey_p1_meter.mjs

3. Restart Z2M and enable pairing

LED

Blue breathing = pairing, green = connected, green blink = telegram rx, purple pulse = OTA, red = no P1 data

OTA Updates

After the initial flash, future updates can be done over-the-air through Zigbee2MQTT using the .ota file from the release page.

Exposed Data

Attribute	Unit	Description
power	W	Total active power (import - export)
power_phase_a	W	Active power phase A
power_phase_b	W	Active power phase B
power_phase_c	W	Active power phase C
voltage_phase_a	V	RMS voltage phase A
voltage_phase_b	V	RMS voltage phase B
voltage_phase_c	V	RMS voltage phase C
current_phase_a	A	RMS current phase A
current_phase_b	A	RMS current phase B
current_phase_c	A	RMS current phase C
energy	kWh	Total energy consumed (cumulative)
produced_energy	kWh	Total energy returned to grid (cumulative)

Values update on every DSMR telegram (typically every 10 seconds).