What I think you need to do is use the Wemos to calculate the time between pulses and relate that to an hourly rate, then send it as a number to emonCMS as well as the pulse count.
The Wemos doesn’t have a realtime clock, and it could be seconds or days between a pulse. I could change the sketch to either return just a pulse or a time interval - I’m not sure it would generate a useful “rate”.
I was hoping that there is some input configuration which takes an accumulating counter and converts it into a rate.
I can see the “Wh increments to kHh/d” feed but this doesn’t take an accumulating count and I would want a shorter period than days (probably hourly - in which hour did it rain?)
In blue the count of pulses,
In red the “Rate of Change”
In yellow the rate multiplied by the conversion factor
Does it not have some means of generating or recording time intervals? I wouldn’t have thought you needed a true real-time clock, surely you only need repeatability (not absolute accuracy) to determine a pulse rate. As long as you can do that, you subsequently introduce a calibration constant to provide the absolute accuracy.
This is fed from a WeMOS D1 which sends the latest count every 60s via HTTP.
What I want to do using the processing in emoncms, is convert that feed into an hourly measurement.
I’ve tried the “Rate of Change” + “Allow Positive” but that doesn’t seem to work at all (constant zero output).
I’ve tried the “Total pulse count to pulse increment” (output = input).
Any ideas? This must be the same problem as converting a gas or water meter to an hourly consumption?
