We updated the code and now it possible not only to save learned raw codes on the sd card, but also to read and send Pronto codes that are stored on the sd card.
@OldSurferDude yes, you are correct. this sensor is capable of 50A continuous, which safely I would make it working at 40A max., but for such an important load as in your case I would go for a beefier one, like the ACS75x, 77x, but at this point I would also change the node's form factor for space and insulation reasons.
On my application on the RV I have a max. curr. of 13A running on a AWG14-16 cable (European rules for RVs), so I did not ask myself too many questions beside, of course, safety.
About the signal, it will be a sinusoidal signal swinging around Vcc/2.
Vcc can be easily measured internally on the ATmega328. On all my DC sensors I measure Vcc at every loop, just before measuring the ADCs.
Honestly, when the space is not an issue like in my RV, I would rather use a ring core current transformer, and I would get rid of noise, response time, power dissipation, but over all no need to cut any cable.
Long story short, it has been a nice experiment and I used it for 6 months, and then I switched back to my RF-NANO based RS485-Modbus - Mysensors bridge connected to an off-the shelf power analyzer.
Just for fun I attach a pic of my 12Vdc sensors installed on my RV. Forgive me for the spaghetti wiring on the right side, but this is an area that needs improvement.
@Kokosnoot good solution. I remember the discussion in the early days of MySensors. I've powered the radio's for most of my sensors from the 3.3v regulator on the arduino board and for me that works perfect. But for my latest designs I decided to add a separate ams regulator for my radio's like the guys suggested in the beginning. Because you basically want the on board regulator to power the mcu only.