ac_meter Total Watt-hours Exported sign issue

[DooMMasteR]

Version of the custom_component

0.025

Configuration

Describe the bug

ac_meter Total Watt-hours Exported is a huge value, slowly lowering whenever electricity is exported

[dp2008]

Have the same problem with Kostal Smart Energy Meter
there seems to be a fix for openHAB but nothing for HA:
https://community.openhab.org/t/solved-wrong-values-with-modbus-and-kostal-smart-energy-meter/99785

see last comment form Oct 2022:
the Kostal SEM reports Exported Real Energy as signed int32 instead of unsigned int32, which makes it report bad values.
Same happens in Home Assistant and with the official Sunspec verification tools.

[DooMMasteR]

Yeah I already tried to get KOSTAL to fix the issue in firmware, but they are super shitty at supporting their products.

[guidoffm]

I have the same problem with the Kostal meter. I found a workaround, until a compliant firmware is available: You can install the Node Red add-on. Then, you can read out one of the wrongly interpreted values, convert it to the correct value, and then send the corrected value to a new virtual sensor in Node Red.

The conversion function is quite simple:

function convert(v){
    return -(v << 0);
}

The << operator converts the uint32 to int32, and the - sign makes the value positive again.

[Canonip]

My workaround of Kostals shoddy programming is the following:
total_increasing is important, otherwise it won't show up in the energy dashboard

template:
  - sensor:
      - name: "Ksem ac_meter Total Watt-hours Exported Corrected"
        unique_id: "ksem_ac_meter_total_watt_hours_exported_correct"
        device_class: energy
        state_class: total_increasing
        unit_of_measurement: Wh
        state: >
          {% set value = states('sensor.ksem_ac_meter_total_watt_hours_exported') | int %}
          {{ 4294967296 - value }}

[DooMMasteR]

Yeah, I am really disappointed that they still have not fixed this fundamental issue.

I am now using the readout of a Deye inverter that we also added to our installation, that has a separate rs485 meter.