MQTT items not reading value 0 from broker

Configuration
1

Dear all,

I have a problem with mqtt items from my DSRM meter monitor program. It pushes the current power usage from my electricity meter to my mqtt broker.

I have configured these items in my config files:

- platform: mqtt
    state_topic: "dsmr/reading/electricity_currently_returned"
    unit_of_measurement: "KW"
    name: DSMR Returned
    device_class: power

  - platform: mqtt
    state_topic: "dsmr/reading/electricity_currently_delivered"
    unit_of_measurement: "KW"
    name: DSMR Delivered
    device_class: power

The problem is that a value of 0 does not work? If I restart home assistant and it connects it uses values bigger than 0 immediately, but topics that have a value of 0 stay on unknow until it changes and then the sensor picks it up.

Also, if my installation is returning power to the grid (for example 1KW). And i put something on like a electric heater, the delivered value shoots up. And in MQTT returned goes immediately to 0. But the sensor does not pick the 0 up and thus stays on 1KW returning while the other sensor says 2KW delivered for instance.

Could this be a problem in my home assistant config, or the way my dsmr monitor pushed values to MQTT?

Many thanks for any hint.

Best regards,
Wouter

2

First thing to do would be to use MQTT Explorer to see what values are being published an in what format. You may need a value_template.

3

Thanks,

I did that and the value 0 is posted there.
image

I also set the flag “force_update: true” on my mqtt items. This seems to be a little better, It receives the 0 value now, but sometimes takes a while to receive it.

I also have a filter on it that limit it on 1 update per minute (the original values update 1 time per second and are excluded from the recorder)

  - platform: filter
    name: DSMR Returned 1min
    entity_id: sensor.dsmr_returned
    filters:
    - filter: range
      lower_bound: 0.0
      upper_bound: 10000.0
    - filter: time_throttle
      window_size: 00:01

This filter has now a value of 0.004 KW last changed 30 min ago. The last change from the original item is also from 30 min ago but last change is to a value of 0.

image

I’m using the 1min filtered items on a graph, but they almost never go to 0. (another problem than the one above, but i think if I fix the 0 value problem this might also get fixed)

Thanks for the input.

Wouter