New to LoRa: what do I need to send machine data home?

Projects General Guidance
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I never worked with LoRa... but bought, what I thought to be the right modules, for my project.

What is the project?

I have an electric digger that has no electronics, as far as a display or sensors go.
So I have installed DS18B20s at the hydraulic pump, the hydraulic oil cooler, and ambient air. I also installed a pressure sensor in the main pressure line. And tapped into the BMS to read the state of charge of the battery.

I have programmed an hour meter, and connected a LCD 20 x 4 display, showing the values for the sensors mentioned above.

So far so good.

I now have this idea to let this Arduino controller (currently a R3 UNO, but can replace with a R4 Maxima) 'phone home' via LoRa.
Hence, I bought a bunch of these "SX1278 LoRa Module 433M Ra-02" modules.

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I also downloaded the LoRa library...

... however, I am not sure which communication mode to use.

All I would like to do is have the digger's controller send data to the home base 300 meters (1,000 feet) away... yes, there are some trees in the way; the module claims 10 km; if it can do one I will be happy.

May I kindly ask for advice about which of these I should use to get started?
My guess would be LoRaSenderNonBlocking.

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Is there anything else I need to watch out for?

  1. I have read on the forum, that one shouldn't change the sync word (whatever that is).
  2. Also, the seller says supply V is 3.3 to 5 V, while the LoRa README says these modules run on 3.3 V. I reckon I need to put some level shifters between the Arduino and LoRa module.
  3. The seller also states 1W, meaning at 5 V, I need 200 mA... that 3.3V pin will not supply that. I am reading 50 to 150 mA.
2

Just start with the Sender and Receiver examples.

Using a 3.3V Logic Level Arduino is much easier than using a 5V Logic level UN0,no logic level conversion or power supply issues.

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3

What hardware will you have at “home base” to receive the Lora transmission?

And what will you do with the info when it gets there? A local LCD display? Send it to the cloud so you can read it on your phone if you’re away from home?

You can get Arduino models with Lora on board so you don’t have to worry about 3.3V to 5V issues. Or you could get a pair of Heltec Lora Wifi modules that have Lora, Wifi and a local display all on one board.

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Sounds like a good idea; will check, if I have any of these. (Mini).

Well, I thought of using another UNO, and push it to Graphana... or simply track the hours in MySQL. Not sure yet. I could track the temperatures, simply to understand where the min/max numbers are going...

I mainly want to test the feasibility and reliability of transmission given the low module cost.

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5

Point to point LoRa is easy to set up and works well in my experience. 300m should be a piece of cake.

Even between two different devices it works reliably. I use an Arduino MKR1310 for the field end (because it has onboard Lora radio and ultra low power conumption) and an ESP32-based Heltec Wifi Lora v3 for the base station (because it has wifi and Lora on the same board).

Even though it’s a different Lora library at each end it worked perfectly first time. Seems to be a good technology well implemented and you should have no problems getting it working.

You might want to check if the Lora radio frequencies are legal for your country.

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Assuming you're already using MySQL, I'd be strongly inclined to push the data there; for now you'll figure out what you want to do with it later on.

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Some of those modules use different pin dimensions. I had to get some 'flexy pin adapters' to make a usable board. Check what frequencies are legal. I have a few bare modules but also 2 of the Heltec V3 WiFi/Lora units with small screens. You will easily reach 300 ft.

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