Archived Forum

Hi Robert ,

Yes you correct you would need 3 x emonTx's and 9 CT's. One Nanode can receive data from multiple emonTx's. We have written some Nanode firmware for this:  https://github.com/openenergymonitor/NanodeRF/tree/master/nanodeRF_recieve_multiple_emontx

Each emonTx would have to be on the same network group and have a different node ID. The Nanode then extracts the node ID from the RFM12 packet to separate the signals. For this to work you will have to use the line 

rf12_sendStart(rf12_hdr, &emontx, sizeof emontx, RADIO_SYNC_MODE); - with hdr info

to send data from the emonTx. Its currently commented out in the emonTx firmware. The line 

rf12_sendStart(0, &emontx, sizeof emontx);

uses slightly less power by not sending the node ID if its not needed. 

Yes the emonTx can use the 868Mhz modules. You will need to change the line

#define freq RF12_433MHZ

to 868Mhz. We use 433Mhz since thats whats available in the UK and they work worldwide. You will also need a JeeLabs RFM12 breakout board for the Nanode to receive the data. This will also need a 868mhz module. We can supply the PCB for this.

Good luck, Glyn.  

Hi Glyn,

Sounds good! I already have the Jeelabs PCBs+modules, so I'll just need a few more for the emonTXes. I'll ponder the GBP 180 for a while, and will contact you as soon as I'll get myself over that hurdle :)

Cheers,

Robert

Why not build up slowly, get one unit and get that up an running and talking to your Nanode before committing to a big order.  

Hi Glyn,

Makes sense. I'll contact you about pricing + shipping. Thanks again for your input :)

Cheers,

Robert

Great thought!!!! Looking forward for the implemention of the kit.

vpn

I tried to convert the emontx kit and after some time i succeed...  Now I am very pleased with the results..

vpn service

Hello

I'm also currently trying to get a second emontx talking to the Nanode but when I put in line

rf12_sendStart(rf12_hdr, &emontx, sizeof emontx, RADIO_SYNC_MODE); - with hdr info

then it says RADIO_SYNC_MODE was not declared in this scope.  I realise there is something I've missed, but cannot figure what it is?

What I have done is taken the standard emontx program and commented out all power lines and put in lines to read 3 x DS18B20 temp sensors which all works fine when I leave the node ID as 10 (the other/original emontx not powered up).  This prints correctly to serial and also displays correctly on emoncms.

When I change the emontx node ID to 11 and also the NanodeRF to look for 11 then it also works.

But when I try to look for both emontx's on nodes 10 (original with 2 CT's and AC/AC adaptor etc.) and 11 (new with only 3 x DS18B20's) then it all goes wrong with the Nanode repeatedly printing the DHCP Status : 1, and only a partial IP address.

Also this link is no longer there -  https://github.com/openenergymonitor/NanodeRF/tree/master/nanodeRF_recieve_multiple_emontx  

Can anyone help with any pointers on getting both my emonTx's communicating with the NanodeRF at the same time?

Thanks

Dennis

Hi Denis

It looks like the link has been moved to https://github.com/openenergymonitor/NanodeRF_ethershield

I am only using 2 emonTX's to connect to the nanode. I haven't looked at the code yet, I'll let you know how I go.

Peter.