Strange rule calculation fluctuations

[rossko57]

@Karol

values of those 3 item came from 2 different power meters

mm, that is difficult to solve, how to “synchronize”.
What to take account of depends very much on what your readings and calculation mean.

This might be of use in your situation, or at least suggest ideas -

Asynchronous Events to Synchronous Event

Problem Statement At times we want to process events that happen asynchronously but only after we have recent data from a set of events. This can be difficult to implement without a lot of custom programming. As an example, MQTT does not guarantee the order of receiving messages. So if we need to process data from MQTT and we only want to do that when a recent set of MQTT messages has been received, we need to do a lot of work to track the timing of those messages. Concept Asynchronous to Sync…

or might all be as simple as just choosing the right rule trigger.