Hi,
I just published on github (https://github.com/gtortone/MySensors-Efergy-e2) my last work about integration of Efergy e2 power meter with MySensors. The Efergy e2 electricity monitor (http://efergy.com/it/products/electricity-monitors/e2-classic) provides a sensor that wirelessly sends information about the amount of electricity you are using to the display monitor. The monitor converts this into kilowatt-hours.

This sketch use a JeeNode v5 (http://jeelabs.net/projects/hardware/wiki/JeeNode) equipped with 433/868 MHz RFM12B module (www.hoperf.com/upload/rf/RFM12B.pdf) configured in OOK mode to capture wireless data (on pin D3) and forward it through NRF24L01+ with MySensors library.

Comments and suggestions are very welcome !

Regards,
Gennaro

p.s. photos will be published soon !

Photo #1: Efergy E2 OOK signal decoded by Zeroplus logic analyzer

Photo #2: JeeNode module with RFM12B radio module

Photo #3: NRF24L01+ JeeNode shield pluggable on SPI header of JeeNode

Photo #4: Final result !

Photo #5: Detail of RFM12B Data pin routed to D3 in order to perform software OOK decoding

Photo #6: Efergy power meter display shows same value of software !

Photo #7: First data gathered by Home Assistant (https://home-assistant.io) on Raspberry PI 3

Some notes:

1. I'm using a RFM12B radio module tuned for 868Mhz equipped with 433 MHz antenna... but everything goes fine due to RFM12B has frequency tuning

2. I plan to do another setup using a simple 433 Mhz receiver or other Hoperf 433 Mhz receiver module (RFM12B are obsoleted modules)

Hi @korttoma,

I did not tested cheap 433 MHz modules yet... I will receive a couple of them next week !
anywai RFM12b is a great module that has interesting features like frequency tuning and adjustable gain...

If I will have updates on cheap modules I will update this thread !

@korttoma

Hi, I have these modules:
http://www.banggood.com/433Mhz-RF-Transmitter-With-Receiver-Kit-For-Arduino-ARM-MCU-Wireless-p-74102.html?rmmds=search

the range is only few centimeters... I will try to do some antenna tuning but I don't expect any significative improvement.

If you want to try with your RXB6 module the code is always the same, you have only to remove the configuration code lines related to RFM12b configuration;

@korttoma Hi, I just returned to play with Efergy and Arduino. I realized that debug messages on UART reset the micro. Now I'm skipping (with a #define DEBUG and #ifdef) all debug messages and it seems to work fine. But take into account that now I'm not using any radio module... just to test the firmware.

@korttoma

Hi,
at the moment I'm defining some things in order to use RFM69 modules...
in the past, on my NRF24L01+ I was using 10 uF capacitor but I had same problems of "stop responding"...

Hi @korttoma,

the value 65535 or 32768 often is used as multiplier from sensor that send metric;
usually when you have to send a "small" float value (temperature, current) you can send it as integer
multiplied by a big constant instead of sending it with a float value converted in binary...

I just refined my formula with this that is more close to formula I found for my Efergy using a small
constant:

current = 18348 / 32768 / pow(2, 255-254 + 1) = 0.139 A
current = 17693 / 32768 / pow(2, 255-255 + 1) = 0.269 A
current = 28835 / 32768 / pow(2, 255-255 + 1) = 0.439 A

Hi @korttoma,
take a look to this decoding based on your collected data for 30W, 60W and 100W;

everything seems to be ok !!

Regards,
Gennaro

p.s. I checked in your profile that you live in Finland and power voltage is 220/240 V

• bytes #1: 0x09 fixed value
• bytes #2: 0X50 fixed value
• bytes #3: 0x2E fixed value
• bytes #4: 0x40 fixed value
• bytes #5: current MSB
• bytes #6: current LSB
• bytes #7: exponent
• bytes #8: CRC
• current detected = ((MSB << + LSB / 65535) / pow(2, (255-exponent))

30 W = 0.13 A (@220V)

9 - 0x09
80 - 0x50
46 - 0x2E
64 - 0x40

71 - 0x47
172 - 0xAC
254 - 0xFE
184 - 0xB8

0x47AC = 18348

current = 18348 / 65535 / pow(2, 1) = 0.139 A

60 W = 0.26 A (@220V)

9 - 0x09
80 - 0x50
46 - 0x2E
64 - 0x40

69 - 0x45
29 - 0x1D
255 - 0xFF
40 - 0x28

0x451D = 17693

current = 17693 / 65535 / pow(2, 0) = 0.269 A

100 W = 0.45 A (@220V)

9 - 0x09
80 - 0x50
46 - 0x2E
64 - 0x40

112 - 0x70
163 - 0xA3
255 - 0xFF
217 - 0xD9

0x70A3 = 28835 (10)

current = 28835 / 65535 / pow(2, 0) = 0.439 A

Hi @korttoma,
happy to read that you are getting "reasonable" values from RFM12B !!

but I agree that in your case the decoding protocol needs some refinements...
just a question: your line voltage is 110 or 240 ?

take into account that from Efergy current sensor you get the value of "current" and
not "power" than for 30W expected value from data is (V/30) [Ampere]...

@korttoma

Hi, I have these modules:
http://www.banggood.com/433Mhz-RF-Transmitter-With-Receiver-Kit-For-Arduino-ARM-MCU-Wireless-p-74102.html?rmmds=search

the range is only few centimeters... I will try to do some antenna tuning but I don't expect any significative improvement.

If you want to try with your RXB6 module the code is always the same, you have only to remove the configuration code lines related to RFM12b configuration;

@korttoma

Hi,
you need to connect RFM12b module to Arduino following this schematic (you can avoid to connect IRQ line...)

http://jeelabs.net/attachments/download/331/jlpcb-128.pdf

after this cabling you need to connect RFM12b DATA pin to Arduino D3 pin (you can select a different pin but modify
code accordingly...)

only after this you can use the Mysensors-Efergy-e2 sketch (https://github.com/gtortone/MySensors-Efergy-e2) to get
RF data;

I tested my code with cheap RF modules (I received them some days ago) but the performance of these modules are very
poor... I will try to do other work on cheap RF modules in the future...

Thanks !

Hi @korttoma,

I did not tested cheap 433 MHz modules yet... I will receive a couple of them next week !
anywai RFM12b is a great module that has interesting features like frequency tuning and adjustable gain...

If I will have updates on cheap modules I will update this thread !

@skywatch
I meaning that often is also useful to check cable two (or three) times !
but if you already did it... ok !

@skywatch
Hi, options for "configure" are ok, I suggest you to double check your cabling !