Howto calc device attributes to variable / Sum database values

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Hello,
i finally got my MQTT running and logging my energy meter of my house.
The energy meter sends out 250Impulse/kWh. I fetching this with a light sensor attached to a ESP8266 running ESPEasy. The light sensor counts up 2 for every impulse of the energy meter (blinking LED is one impulse, but sensors counts LED On = 1, LED Off = 1)
In ESP Easy i multiply this with 2 and send this to my Mosquitto broker every 5 minutes.
So mosquitto receives every 5 minutes a value how many energy (W/h) was used in the last past minutes.
pimatic-mqtt gets this value and shows it.
This works very well for me.
Now i like to use this value (it’s actually a attribute of a device) to graph also

• Energy used last hour
• Energy used last day
• Energy used last month

Is there a way to sum all values stored in the database for the 5min counter up to something else?
Or -
how to transfer the attribute of a device to a variable?

Thank you

@Raducanu said in Howto calc device attributes to variable / Sum database values:

how to transfer the attribute of a device to a variable?

Regarding the last question, this can be done easily. The exhibited attribute values of a device can be seen in the list of variables. Amongst these is $TXL.pressure in my case which is the pressure value of a weather device. In the following example a variable is created with an expression to perform a pressure normalization.

There are a few functions you can use as part of an expression such as min, max, avg, pow, and round. Moreover, you can use arithmetic operators +,-,/.%,* to perform a calculation. Hope, this helps. Regarding the MQTT-related part of your questions I am sure @wutu will be able to help you further.

The problem is, that my device is not listed in the list of variables.
I can select the attributes in the rule editor, but they are not visible in the variables list (i guess under Objekteigenschaften (guess object attributes in english)) and i also cannot use it as a regular expression.

@Raducanu said in Howto calc device attributes to variable / Sum database values:

The problem is, that my device is not listed in the list of variables.
I can select the attributes in the rule editor, but they are not visible in the variables list (i guess under Objekteigenschaften (guess object attributes in english)) and i also cannot use it as a regular expression.

Restarted pimatic, device was created…