Sensors to detect voltage

rejas

As a boat enthusiast I have interest in monitoring the voltage of my battery banks during the winter. I do this already in the summer with a Raspberry Pi but in the winter that consumes too much energy. I'm looking for a wireless sensor with some range so that I can have a gateway in the boatyard and a wireless sensor in the boat. Preferably LoRa.
So I need a LoRa (or other suggestion) sensor that can measure voltage (about 10-15V). If it is cheap and have a good IP-rating that is a plus. Any suggestions?

rejas

The optimal solution (might be impossible demands of course) is a low price rugged sensor that measures dc voltage, humidity and temperature. Even though connected to a DC-source it is preferably self powered via internal battery.

rejas

I am bumping this thread again. I'm searching for a sensor, preferably LoRa but all are of interest, that measures as many a possible of.

Need to have:

Voltage 10-15V on external powersource (the device should preferably not be powered from this source)
Temperature
Humidity

Nice to have:

Tilt
Door sensor (or external input)

fredrik

@Mats do you have any idea? Maybe the https://www.elsys.se/en/elt-lite/ sensing the voltage over a voltage divider?

rejas

This project took a somewhat unforeseen turn. I did not find a sensor matching my description without adding extra components to it. I'm sure that they exists but I found a more interesting way.

This weekend I have spent some time testing and learning new things and I love it! The result is a LoRaWan sensor meeting the demands above. At a very low cost I have the sensor.

I used a Raspberry Pi Pico, a SX1262 LoRa Chip module and some resistors. Soldered it to a PCB board and wrote some code. Still in the experimental phase and some things to add to reduce the battery consumption. My target is at least a year on battery. I also need a watertight case for it.

I'll probably tell more in the future. It's a hobby project so it will take some time.

Here is the current state (yes, I know the sticker with polarity is wrong :-))