question

I'm trying to connect my DSMR reader data to the Victron by using MQTT.
Below is the initial question I asked to dbus-mqtt-devices:

I'm trying to create a small script which reads data from DSMR-reader send to a MQTT broker, and send it to the victron MQTT broker.
So far so good, and I've mapped out most of the values correctly. I've followed I've read: https://github.com/victronenergy/venus/wiki/dbus#grid-and-genset-meter to map all the data I have from DSMR to the corresponding Victron topics.

After running the script the entire day, I noticed my Victron values weren't updated when I was sending power back to the grid.

The snippet sending data to the topic in Victron is:

        elif msg.topic == f"{DSMR_TOPIC}/reading/phase_currently_returned_l1":
            wattage = float(msg.payload.decode("utf-8")) * 1000
            publish_to_victron(f"W/{portal_id}/grid/{device_instance}/Ac/L1/Energy/Reverse", wattage)

This value is in Kw, so I multiply it by 1000 to get the W value, which I then publish to the Victron bus on Ac/L1/Energy/Reverse topic. But this doesn't seem to do anything.

If I manually try to send the message on this topic, nothing happens.
The only way I can get the victron to display a negative number, is by sending data to the /Ac/L1/Energy/Forward or /Ac/L1/Power with a negative sign in front of it (e.g. -2).

My main questions:

• What is the correct way to use the Reverse topic?
• Should I calculate the negative number, and publish that to the /Ac/L1/Energy/Forward topic?

I'm sending it as Json, using separate function:

def publish_to_victron(topic, value):
    payload = json.dumps({"value": value})
    victron_client.publish(topic, payload)
    print(f"Published to Victron: {topic} with payload {payload}")

For example a message published would be:
Published to Victron: W/b827eba77875/grid/1/Ac/L1/Energy/Reverse with payload {"value": 0.0}

I see all values correctly on the bus, and it works for all my loads.
But for some reason as soon as I start delivering power back to the grid, it doesn't turn negative.

I hacked around a bit, and tried different stuff before actually moving to the grid sensor. But I'm by no means an expert in this.

Steps I took to make sure I have a basic understanding:

1. Listened on the Victron bus for a while to see what's going on.
2. Try to inject some payload to get an ID using MQTT Explorer (publishing to the device/name/Status topic)
3. Start publishing some data on the needed topic to show data in the Victron
4. After figuring it out by hand, start hacking away in Python
5. Watching result, and be satisfied with the initial script
6. See weird behaviour when returning solar.
7. Hack around how to get value to display negative (sending a payload with a minus (-) sign in front)
8. Question if this is the correct way to send payload, or I'm just making a rookie mistake.

Hopefully this clarifies it a bit, and how I got to this point.

And if I use `dbus-spy` I'm able to see the values on the reverse topic.

I've already done a lot of troubleshooting with the maintainer of dbus-mqtt-devices, but it looks like it's related to Victron. For reference: https://github.com/freakent/dbus-mqtt-devices/discussions/92#discussioncomment-8530877