Anyone running home automation stuff?

Hi All,

Since getting my Pi2b running OMV as a baby wired fileserver (with a

3TB USB laptop drive) and my Pi1b as a wireless print server for my Dymo 450 LabelWriter, now I'm running Domoticz (wirelessly) on my Pi3b.

The latter arose from a question elsewhere re being able to monitor / log my domestic electricity usage, more for the fun / interest than anything more scientific and the RPi / Domoticz combo was recommended.

So, now it's running I'd like to try some stuff on it and it seems that many of these remote sensors run on 433 Mhz, including the 'lectrisave' Cent-a-meter (/ Owl & other re-badges no doubt) CMR113A transceiver I already have here apparently.

It also seems the matching RF unit that is used at the RPi end is the 'Rfxcom RFXtrx433E USB HA' but they aren't 'cheap':

and a lower cost, more d-i-y solution using an Arduino (can I say that here ) and either a dedicated transceiver board or the components (transmitter / receiver) d-i-y'd onto the Arduino (typically Mega).

So, because this is all very new to me and spurred on by being able to get it installed and running on the Pi, I was wondering if any Pi users here had such a (or similar) solution running and could share any thoughts or general advice please?

As I already have a Mega spare (we use them on the 3D printer) I wouldn't mind trying the d-i-y transceiver solution and then I'm guessing I could get a cheap 433 external thermometer or wind speed indicator along with interfacing my household power meter?

Cheers, T i m

Something worth checking is exactly what's meant by '433MHz'. First thing is the band: do they all work on the same frequency, or do you have to select somehow? Also, I see lots of things that do some kind of pulse protocol (ASK? FSK?). Are they all compatible with each other, or do you need to match receiver with transmitter?

For instance, the Energenie power measuring kit I mentioned in the other thread has two modules:

This one is a one way device for switching power sockets controlled by a GPIO:

This one is a two way device for switching and receiving power measurements:

based on an RFM69 module connected by SPI.

What I don't know is: is the air interface the same, and thus they're interchangeable, or do you need to match the modules at each end?

(In the Energenie case I think they are both able to control the same switch-only devices, but it might not hold for all products)

Theo

Quite. This is why I though I'd ask here.

Good questions Theo.

Interesting.

Same thoughts as were crossing my mind. You see what sound like different brand names mentioned and a dangerous assumption would be that they all comply with some standard. I'm pretty sure that's unlikely to be the case but it's also possible that some of these 'clever' Wireless interfaces could deal with more that one of them (assuming as you suggest that they are all on the same frequency).

Understood.

Whilst I am interested to dip my toe in this water it looks like it could be full of crocodiles. ;-(

Cheers, T i m