emonTx "Keys"

Sorry to ask such a dumb question, but how do I determine what the Keys refer to? I’ve just set up my 4th emonTx (c/w ESP wifi widget), and it reports through to my Emonpi.local fine. But under the Latest Data tab it shows this. I am fairly sure P1 is the CT1 input (the only one I have anything plugged in to, but what is MSG, E1 and pulse ? (I do have an AC adapter fitted for measuring Vrms).


The way to find out is to look at the sketch:

“MSG” is a count of message number, it increments by one for each message sent. This allows missing data to be identified (but never restored, unfortunately).
“Vrms” is the voltage in 1/100ths of a volt.
“P1” - “P4” are the real power value for the 4 c.t. inputs in watts.
“E1” - “E4” are the accumulated energies for the 4 c.t. inputs in watt-hours.
“T1” - “T3” are temperatures in 1/100ths of a degree Celsius.
“pulse” is an accumulating count of pulses as detected by the pulse input.

The accumulated values start from zero when the sketch starts or is reset. emonCMS is able to handle that reset in most circumstances.

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Here are the lines in the EmonTx firmware that set these values:, it’s not super clear, the names are kept short to reduce bandwidth consumption.

It would be good to add documentation to explain the input names, I’ve created an issue here to keep track of this


@haffle, update in master has included the definitions in the documentation.

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@TrystanLea, on processing, I have…




Is this correct?