This post describes how you can get Homewizard P1 meter telegrams from your DSMR smart meter into DSMR Reader using Home Assistant automations and scripts.
Until now I have been using a Raspberry Pi and a P1 USB cable to retrieve the smart meter telegrams.
In 2025 I hope to install a Homewizard plug-in battery. A Homewizard P1 meter is then necessary.
(I have also instructions how to send Homewizard P1 telegrams to xirixiz/dsmr-reader-docker using DSMR Reader plugins. See DSMR Reader Docker and Homewizard P1 meter integration)
Introduction
Homewizard P1 telegrams can be sent to DSMR Reader as follows:
- use the Homewizard API /api/v1/telegram to get a raw telegram
- use the DSMR Reader v1 API /api/v1/datalogger/dsmrreading to inject a telegram into DSMR Reader
We will use only Home Assistant REST commands to do the integration.
What you need
- working instances of
- Home Assistant
- DSMR Reader
- a Homewizard P1 meter
- plugged into your smart meter
- already configured and visible in the Homewizard Energy app
- local API enabled
- IP address Homewizard P1 meter
- IP address DSMR reader
- API key DSMR Reader
REST commands
In your Home Assistant configuration.yaml file create the following REST commands
rest_command:
get_hw_p1_telegram:
url: "http://{{ip}}/api/v1/telegram"
method: get
dsmr_push_telegram:
url: "http://{{ip}}/api/v1/datalogger/dsmrreading"
method: post
payload: "telegram={{telegram}}"
headers:
"Authorization": "Token {{ api_key }}"
"Content-Type": "application/x-www-form-urlencoded"
Script to get a Homewizard raw P1 telegram
Create the following script
alias: Get Homewizard P1 telegram
sequence:
- service: rest_command.get_hw_p1_telegram
data:
ip: "{{ip}}"
response_variable: response
- stop: rest command executed
response_variable: response
fields:
ip:
selector:
text: null
name: ip
description: IP address Homewizard P1 meter
required: true
mode: queued
max: 100
You can use this script in Developer Tools / Services to check if you can get a telegram successfully.
Script to poll and process a P1 telegram
Create a Home Asssistant script
In the code below:
- replace 1.2.3.4 with the IP address of your Homewizard P1 meter
- replace 6.7.8.9:7777 with the correct IP and port of your DSMR Reader
- replace your_api_key with the DSMR Reader API key
alias: Process P1 telegram
sequence:
- service: script.get_homewizard_p1_telegram
data:
ip: 1.2.3.4
response_variable: result
- choose:
- conditions:
- condition: template
value_template: "{{ result.status == 200 }}"
sequence:
- service: rest_command.dsmr_push_telegram
data:
ip: 6.7.8.9:7777
telegram: "{{ result.content }}"
api_key: your_api_key
response_variable: ret
enabled: true
- stop: end of script
response_variable: result
mode: queued
max: 100
Automate the process
Create an automation to fetch a telegram.
DSMR v4 meters publish a new telegram (with electricity information) every 10 seconds (use a trigger of /10).
DSMR v5 meter update every second (use a trigger of /1).
alias: Process Homewizard P1 Telegrams
description: ""
trigger:
- platform: time_pattern
seconds: /10
condition: []
action:
- service: script.process_p1_telegram
response_variable: response
mode: queued
max: 100
