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The idea is to control a water pump that uses an induction motor. By control I simply mean to turn on and off the motor of the water pump.

The setup includes a Lora gateway that transmits the desired action.

From my understanding you have to connect a lora tranceiver module to a microcontroller (like an arduino?). Is this correct?

Concerning the microcontroller controlling the motor I am reading about relays, switches, motor drivers but don't really understand. What is the proposed way to control the AC motor?

Is the configuration different when controlling speed compared to switching on and off?

The motor should be a typical ac induction motor. I do not care about latency, nor precision, even 10+ seconds would be acceptable . The motor will be switched on average once a day .The motor and gateway will both be outside. Lets assume there is only one motor. The maximum distance should be 500 meters on an open field without objects in the way. I would like to use my own network. By the way, is there some other shorter range technology commonly used instead of Lora so as not to mess with cycles etc

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    What exactly is the question here, are you looking for a motor controller or a microcontroller and LoRA radio? And what research did you do before asking the question?
    – hardillb
    Apr 29 at 7:44
  • Sorry for not being specific I have little knowledge on the subject. Your comment was pretty helpful actually. I edited my question
    – Doitsidis
    Apr 29 at 15:07
  • Yes that is correct. You need a relay, Id go with a relay module that already has all the other components you need since you are just getting started.
    – Randomaker
    Apr 30 at 0:57
  • Do you have any specs for the motor? Type of current (AC or DC), voltage, power... it’s more than likely that the electrical specs will indeed require the use of a relay.
    – jcaron
    Apr 30 at 7:31
  • Also what country are you in (this will dictate things like duty cycle limits for LoRa), what network do you use (your own or something like TTN for instance), how often to you need to switch on/off the motor, how many motors are there per gateway, what kind of delay is acceptable to switch the motor on/off, and is it an issue if a command is lost or delayed? Are you indoors or outdoors (both the motor and the gateway)? What distance is there between gateway and motor, and do you have line of sight?
    – jcaron
    Apr 30 at 7:35
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You can look around on the Internet for ready made LoRaWAN end devices that can be used as remote controlled switches. One of those can be the this but you may find others on https://market.thingpark.com.

Based on what you wrote you do care latency. If you accept only ~10s latency, you need a ClassC device that should be connected to the mains power. Battery powered devices are usually Class A devices that can do the swicthing with ~1 hour latency (If you want a long battery life time.)

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  • Well since posting the question I learned the basics of MCUs development boards and other devices. I think RF is best for transmitting something similar to NRF24L01+ which achieved more than 100 meters range without an antenna. So the boards scattered on the field will have a sensor a transmitter and a battery. And they will send the signal to a more powerful raspeberry pi type of device which will draw power from the grid and will have a 4g module, an RF receiver and will also be connected to motor driver. I still have no clue about drivers relays etc.
    – Doitsidis
    Jul 12 at 21:29
  • I also need to research sleep and low power modes. I also have another question. In real world applications, mass produced devices use custom Printed circuit boards with everything incorporated? (in contrast to soldered components I guess, used for prototyping)
    – Doitsidis
    Jul 12 at 21:34
  • My answer asumed that you are looking for a LoRaWAN solution. Now I see that you are trying to build your own hardware and use your own protocol for the communication. LoRaWAN already has a large ecosystem and allows you to get solution of the shelf. If you develop your own hardware an communication protocol, then you have to invest more effort, but you will not depend on an external LoRaWAN network. Regarding the pcb design, there are two approaches: either you design your own pcb including allnecessary components or you use a lora module including the semtech chip + mcu + gpio etc. Jul 13 at 6:14

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