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emonTx receiving inputs from emonTH?

Tags: #<Tag:0x00007fc9c4156a40>

Hi everyone,

I have been using an emonTx V3 for about a year, with 4 CT sensors and logging to with the wifi module.
I would like to also monitor temperature and humidity in several places of my home. Is it possible to transmit from an emonTH to the emonTx, without the need of emonPi/emonBase? I need to do it wireless, but I don’t know if the 433MHz radio of the emonTH will communicate with the emonTx and I will see temperature and humidity as inputs.

Thanks for your help!

Possible, yes. But not “out of the box”, it would involve writing some custom firmware.

You have everything you need, hardware wise, but the emonTx firmware has been written to only send via the RFM module, not receive. In contrast, the emonPi firmware is written to receive and transmit as a base station, but it has some emonpi specific code, it doesn’t conform to the emonESP style of serial output and it has only 2 CT channels. It would be totally feasible to create a firmware sketch using bits of the emonPi and emonTx sketches to enable the emonTx to effectively function as an emonBase with 4 CT’s and output in a format that the emonESP was ok with. AFAIK this has not yet been tried, or if it has, it has not been published/shared as yet, but it is totally doable.

I agree - the most likely reason for the emonTx never (again, as far as I know) having been used as a receiver is because if operated from batteries, the battery life would be very short, as the receiver needs to be listening continuously. If your emonTx is mains powered, that won’t be a concern.

Or indeed to work the receive part of the emonGLCD sketch, which listens continuously for data from an emonTx (and then displays it), into the emonTx sketch.