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Zigbee2mqtt plugin and temp sensor update frequency

Posted: Monday 22 March 2021 13:32
by brjhaverkamp
Hello all,

As I wrote in some previous posts, I am using zigbee21mqtt, the zigbee2mqtt-plugin and some aqara zigbee devices in my home automation.
I was playing with the graphs in dashticz. But I noticed the graph in both Dashticz and Domoticz have a very staircase look.
I dug into this and noticed there are datapoints every 5 minutes. But since the sensors send an update much less frequently, there are a lot of consecutive datapoints with the same value. And this is causing the staircase look.

Below I attached a screenshot. I changed the graph type to barchart to show explicitely how many datapoints there are in the graph. Each red line is a datapoint in the table. But the number of measurements coming from the temperature sensor are actually much less.
Graph.png
Graph.png (117.84 KiB) Viewed 2796 times
Regards,
Does anyone know where the 5minute interval is coming from? Is this domoticz internal? Is this due to the plugin? Is there anywhere to set this? Or should I dig into the code?


Bert

Re: Zigbee2mqtt plugin and temp sensor update frequency

Posted: Monday 22 March 2021 16:57
by waltervl
Normally these kind of Zigbee sensors only send data if the delta reaches a treshold e.g. 1 degree. This to minimize battery consumption.I think Domoticz is registering sensor values every 5 minutes. If no new data is received it wil register the old value (as nothing has changed).

Re: sensor data update frequency and staircase effect in graphs

Posted: Thursday 25 March 2021 9:57
by brjhaverkamp
Hi Waltervi,

Thanks for the explanation. That sounds indeed as what I am observing. The step change is constant, and the timeperiod between measurements is varying.
The source of my question was that I would like my graph a bit nicer and smoother looking line graph. But the 5 minute duplication of the values gets in the way. They cause the staircase effect.
Any suggestion to get around this?


Regards,
Bert

P.S. I have changed the topic . As this has nothing to do with the plugin and is not temperature sensor specific. Not sure how to move this out of the zigbee group to e.g. the dashticz group though.

Re: Zigbee2mqtt plugin and temp sensor update frequency

Posted: Thursday 25 March 2021 11:36
by waltervl
How does these curves look like in the normal Domoticz device log?

PS you will have to change the topic name on the first topic.... (and add Dashticz)