RSCP2MQTT - Bridge between an E3/DC device and an MQTT broker

This software module connects a home power station from E3/DC to an MQTT broker.

It uses the RSCP interface of the device. The solution is based on the RSCP sample application provided by E3/DC and was developed and tested with a Raspberry Pi and a Linux PC (x86_64).

The tool cyclically queries data from the home power station and publishes it to an MQTT broker using these topics.

Supported topic areas are:

• Energy topics for today
• Current power values
• Autarky and self-consumption
• Battery status
• Energy management (EMS) power settings
• Data from yesterday and the current week, month and year
• Values of the power meter (PM)
• Values of the photovoltaic inverter (PVI)
• Values of the emergency power supply (EP)
• Values of the wallbox (WB)

For continuous provision of values, you can configure several topics that are published in each cycle. Default: Only modified values will be published.

Features

• E3/DC wallbox topics
• InfluxDB support
• Topics for temperatures (battery, PVI)
• Idle periods
• System error messages
• Details of the battery modules (DCB)
• Units as InfluxDB tags
• Battery SOC limiter
• Docker images at https://hub.docker.com/r/pvtom/rscp2mqtt
• Dashboard is available
• Configuration of the topics that will be published to InfluxDB (INFLUXDB_TOPIC)
• Multiple battery strings are supported (BATTERY_STRINGS parameter)
• Automatic detection of the number of PVI trackers
• Historical data for past years
• Query of historical daily values
• Multiple power meters
• Switch between wallboxes

Please also take a look at the release notes.

Docker

Instead of installing the package you can use a Docker image.

Prerequisites

• An MQTT broker in your environment
• rscp2mqtt needs the library libmosquitto. For installation please enter:

sudo apt-get install libmosquitto-dev

If you like to transfer data to InfluxDB install the libcurl library:

sudo apt-get install curl libcurl4-openssl-dev

Cloning the Repository

sudo apt-get install git # if necessary
git clone https://github.com/pvtom/rscp2mqtt.git
cd rscp2mqtt

Compilation

To build a program version without InfluxDB use:

make

To build a program version including InfluxDB support use:

make WITH_INFLUXDB=yes

Installation

sudo mkdir -p /opt/rscp2mqtt
sudo chown pi:pi /opt/rscp2mqtt/

Adjust user and group (pi:pi) if you use another user.

Copy rscp2mqtt into the directory /opt/rscp2mqtt

cp -a rscp2mqtt /opt/rscp2mqtt

Configuration

Copy the config template file into the directory /opt/rscp2mqtt

cp config.template /opt/rscp2mqtt/.config

Please change to the directory /opt/rscp2mqtt and edit .config to adjust to your configuration:

cd /opt/rscp2mqtt
nano .config

The configuration parameters are described in the file.

The prefix of the topics can be configured by the attribute PREFIX. By default all topics start with "e3dc". This can be changed to any other string that MQTT accepts as a topic, max. 24 characters. E.g. "s10" or "s10/1".

If your system has more than one battery string (e.g. S10 Pro), you have to configure the parameter BATTERY_STRINGS accordingly. Battery topics that belong to a battery string are extended by the number of the battery string. Battery modules (DCB topics) are numbered consecutively.

Find InfluxDB configurations in InfluxDB.

The parameter FORCE_PUB can occur several times. You can use it to define topics that will be published in each cycle, even if the values do not change. To check the definition, look at the log output after the program start.

Logging can be configured for messages that the home power station output in response to a request. Messages are collected including a counter for the number of occurrences. The errors will be logged in a bundle at midnight, at the end of the program or by querying with e3dc/set/log/errors. This reduces the number of error messages. To do this, set in the .config file: LOG_MODE=BUFFERED. You can also switch off the logging of such messages completely with LOG_MODE=OFF. If every event is to be logged: LOG_MODE=ON.

Program start

Start the program:

./rscp2mqtt

or in verbose mode

./rscp2mqtt -v

or to show the help page

./rscp2mqtt --help

If everything works properly, you will see something like this:

rscp2mqtt [3.23]
E3DC system >192.168.178.111:5033< user: >your E3DC user<
MQTT broker >localhost:1883< qos = >0< retain = >false< client id >✗< prefix >e3dc<
Fetching data every second.
Requesting PVI ✓ | PM (0) | DCB ✓ (1 battery string) | Wallbox (0) ✗ | Autorefresh ✓
Log level = 0
Stdout to terminal

[2024-05-12 19:00:00] pid=30230 ppid=1 RscpMqttMain.cpp(2952) Connecting to server 192.168.178.111:5033
[2024-05-12 19:00:00] pid=30230 ppid=1 RscpMqttMain.cpp(2959) Success: E3DC connected.
[2024-05-12 19:00:00] pid=30230 ppid=1 RscpMqttMain.cpp(1896) RSCP authentication level 10
[2024-05-12 19:00:00] pid=30230 ppid=1 RscpMqttMain.cpp(2428) Connecting to broker localhost:1883
[2024-05-12 19:00:00] pid=30230 ppid=1 RscpMqttMain.cpp(2440) Success: MQTT broker connected.

Check the configuration if the connections are not established.

Notes: In the following examples I assume that the MQTT broker runs on the same machine as rscp2mqtt under port 1883. If the MQTT broker runs on another server, please use its name instead of localhost and change the port if it is different. The default prefix e3dc is used for the topics. Please adjust the calls if you use a different prefix.

If you use the Mosquitto tools you can subscribe the topics with (here without user / password)

mosquitto_sub -h localhost -p 1883 -t 'e3dc/#' -v

Daemon Mode

Start the program in daemon mode:

./rscp2mqtt -d

The daemon can be terminated with

pkill rscp2mqtt

Be careful that the program runs only once.

Systemd

rscp2mqtt can be managed by systemd. For this purpose, copy the file rscp2mqtt.service to the systemd directory:

sudo cp -a rscp2mqtt.service /etc/systemd/system/

Configure the service sudo nano rscp2mqtt.service (adjust user 'User=pi'), if needed.

Register the service and start it with:

sudo systemctl enable rscp2mqtt
sudo systemctl start rscp2mqtt

Check log output

journalctl _SYSTEMD_UNIT=rscp2mqtt.service

Device Control

rscp2mqtt subscribes to the root topic "e3dc/set/#" and forwards incoming requests to the home power station. In this way, the device can be controlled, additional data can be queried and changes can be made to its configuration.

Battery Charging

Start battery charging manually (payload is the energy [Wh] to charge)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/manual_charge" -m 1000

Weather Regulation

Set weather regulation (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/weather_regulation" -m true

Power Limits

Set limits for battery charging and discharging (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_limits" -m true

Set the charging and discharging power limits in [W]

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/max_charge_power" -m 2300
mosquitto_pub -h localhost -p 1883 -t "e3dc/set/max_discharge_power" -m 4500

Idle Periods

Set idle periods to lock battery charging or discharging

Note: The set operations will work only if the idle period functionality is turned on (via the S10 display).

Parameters:

• Day: "monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday" or "today"
• Mode: "charge" or "discharge"
• Active: "true" or "false"
• Period: "hh:mi-hh:mi"

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/idle_period" -m "today:charge:true:00:00-23:59"

With the topics "e3dc/ems/charging_lock" and "e3dc/ems/discharging_lock" you can check whether a lock is currently active or not.

Battery SOC Limiter

The SOC limiter can be used to conveniently control the charging or discharging of the house battery. It uses the Idle Periods described previously.

Maximum SOC

When the maximum SOC value is reached, the battery charging process is stopped.

Minimum SOC

The battery charge level does not fall below the minimum SOC value. When the SOC is reached, discharging stops.

Home Power

When the house power is above the set value, discharging will stop. This can be used, for example, to prevent charging the electric vehicle from the house battery (when using a non-E3/DC wallbox that cannot be controlled directly by the device).

Set the minimum SOC to limit discharging the battery [%]

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/soc" -m 30

Turn off the limiter for discharging the battery

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/soc" -m 0

Set the home power value which stops discharging the battery [W]

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/by_home_power" -m 7000

Reset the home power value which stops discharging the battery

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/by_home_power" -m 0

Reset the limiter at the day change

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/durable" -m false

Keep the limiter setting even after the day change

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/discharge/durable" -m true

Set the maximum SOC to limit charging the battery [%]

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/charge/soc" -m 80

Turn off the limiter for charging the battery

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/charge/soc" -m 0

Reset the limiter at the day change

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/charge/durable" -m false

Keep the limiter setting even after the day change

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/limit/charge/durable" -m true

Emergency Power

Set battery reserve for emergency power

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/reserve/energy" -m 1500 # in [Wh]
# or
mosquitto_pub -h localhost -p 1883 -t "e3dc/set/reserve/percent" -m 10 # in [%]

Power Management

Control the power management with "e3dc/set/power_mode":

The functionality can be used to intervene in the regulation of the power management. Caution: This function can be used to bypass a set feed-in reduction. Use this functionality at your own risk.

Automatic / normal mode

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_mode" -m "auto"

Idle mode (number of cycles)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_mode" -m "idle:60"

Discharge mode (power in [W], number of cycles)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_mode" -m "discharge:2000:60"

Charge mode (power in [W], number of cycles)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_mode" -m "charge:2000:60"

Grid charge mode (power in [W], number of cycles)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/power_mode" -m "grid_charge:2000:60"

After the time has elapsed (number of cycles multiplied by the configured interval) plus a few seconds, the system automatically returns to normal mode.

Turn on the functionality in the configuration file .config, add/change the following line:

AUTO_REFRESH=true

Wallbox Control

The commands for controlling an E3/DC wallbox can be found here.

Historical daily data

Historical data for a specific day (format "YYYY-MM-DD") can be queried by

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/request/day" -m "2024-01-01"

Please use the script request_days.sh to request data for a time span.

./request_days.sh localhost 1883 e3dc 2024-01-01 2024-01-13

System Commands

Refresh all topics

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/force" -m 1

Refresh specific topics

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/force" -m "e3dc/history/2021.*"

Log all topics and payloads to the log file

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/log/cache" -m 1

Log collected error messages to the log file

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/log/errors" -m 1

Set a new refresh interval (1..300 seconds)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/interval" -m 2

Turn PM requests on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/requests/pm" -m true

Turn PVI requests on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/requests/pvi" -m true

Turn DCB requests on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/requests/dcb" -m true

Turn SOC limiter on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/soc_limiter" -m true

Turn daily historical values on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/daily_values" -m true

Turn statistic values on or off (true/1/false/0)

mosquitto_pub -h localhost -p 1883 -t "e3dc/set/statistic_values" -m true

Used Libraries and Licenses

• The RSCP example application comes from E3/DC. According to E3/DC it can be distributed under the following conditions: The authors or copyright holders, and in special E3/DC can not be held responsible for any damage caused by the software. Usage of the software is at your own risk. It may not be issued in copyright terms as a separate work.
• License of AES is included in the AES code files
• Eclipse Mosquitto (https://github.com/eclipse/mosquitto) with EPL-2.0
• libcurl (https://github.com/curl/curl/blob/master/COPYING)