hms-mqtt-publisher

This tool fetches the current telemetry information from the HMS-XXXXW-2T series of micro-inverters and publishes the information into an MQTT broker. Please note that it doesn’t implement a DTU, but pulls the information off the internal DTU of these inverters.

How to run

The tool is distributed as source only — for now. You’ll have to download, compile and run it yourself. Please note that configuration of hosts, and passwords is done via config.toml from the current directory. It supports two different output channels. One is a simple MQTT publisher that doesn't follow a particular schema, and the other is made for Home Assistant. It supports auto discovery of devices.

$ git clone https://github.com/DennisOSRM/hms-mqtt-publisher.git
$ cd hms-mqtt-publisher
$ cargo r

image

Docker

The latest release is directly deployable via a docker image from DockerHub. It is built automatically for the following Linux platforms:

The container is configured with environment variables (see Configuration), e.g.

docker run -e INVERTER_HOST=192.168.4.182 -e MQTT_BROKER_HOST=192.168.1.10 dennisosrm/hms-mqtt-publisher

Alternatively, mount a config.toml to /config/config.toml.

Configuration

Settings are read from config.toml in the current directory (or next to the executable) and can be set or overridden by environment variables, for every kind of deployment:

Variable config.toml setting Notes
INVERTER_HOST inverter_host required
UPDATE_INTERVAL update_interval milliseconds, minimum and default 30500
MQTT_BROKER_HOST host of the MQTT outputs required unless set in config.toml
MQTT_PORT port optional, default 1883 (8883 with TLS)
MQTT_USERNAME username optional
MQTT_PASSWORD password optional
MQTT_TLS tls optional, true or false
MQTT_CLIENT_ID client_id optional, used as is; with both outputs enabled -ha and -sm are appended. Default derived from the device id or inverter host
DEVICE_ID device_id optional, see Multiple inverters

Environment variables take precedence over config.toml. The MQTT_* variables apply to the MQTT outputs configured in config.toml ([home_assistant], [simple_mqtt]); without any, they enable both. Empty variables count as not set.

Multiple inverters

Run one instance per inverter and give each a distinct DEVICE_ID (or device_id in config.toml), for example the last digits of its serial number. It may contain letters, digits, _ and -. The device id names the inverter in the Home Assistant entities (hms_<device id>) and replaces the hms800wt2 prefix of the simple MQTT topics. Without it, Home Assistant uses the first 8 characters of the DTU serial number, which are the model and production week and can be the same for several inverters. Leave it unset for a single inverter to keep the existing entity ids.

Each instance connects with its own MQTT client id, derived from the device id or the inverter host, so the instances don't disconnect each other.

S-Miles cloud

Querying the inverter can make it skip uploads to the S-Miles cloud: it uploads about once a minute and skips an upload when it was queried shortly before. Setting update_interval = 60500 (or UPDATE_INTERVAL=60500), as the Home Assistant add-on does by default, lets most uploads through, but depending on the timing some can still be missed.

Ansible (systemd)

You can use the bellackn.homelab.hms-mqtt-publisher role to deploy hms-mqtt-publisher as a systemd service to a remote host. Check the role's documentation to see configuration options and setup instructions.

Note of caution

Please note: The tool does not come with any guarantees and if by chance you fry your inverter with a funny series of bits, you are on your own. That being said, no inverters have been harmed during development.

Known limitations