Gsm 2 way notification switch

[markuk75]

Hello
So I have a project that I need to design
I need to unlock a solenoid in a field but also know it's been unlocked.
There is no power or WiFi

I have the lock working on a timer and a 12v battery with solar charging the battery
But I would like to know the lock has unlocked.
Have been looking at GSM boards but I want an app rather than dialing a number to unlock.

Also like I said I need it 2 way so app would be better.
Not sure how to do that.
There are lots of GSM boards about but only for dialing in to and only 1 way

Mark

 

[Nigel Goodwin]

There are plenty of options, but without available WiFi you would need a GPRS system instead - so a SIM card and subscription for the connection.

Obvious issues are the power requirements, as it needs to be permanently powered up if you want fast access to it, and the cost of the data connection.

For an example of how it can be done, using WiFi at home have a look at:

ESP32 Web Server - Arduino IDE | Random Nerd Tutorials

In this project you’ll create a standalone web server with an ESP32 that can toggle two LEDs using the Arduino IDE programming environment.

randomnerdtutorials.com

There is also an ESP32 variant with a GSM Modem, but bear in mind it's 2G only.

ESP32 SIM800L: Publish Data to Cloud without Wi-Fi | Random Nerd Tutorials

Connect the ESP32 with SIM800L TTGO T-Call board to the Internet using a SIM card data plan and publish data to the cloud without using Wi-Fi (Arduino IDE).

randomnerdtutorials.com

How far away is the field?, does it only need to be accessed from the farmhouse?, does it need to be accessible from anywhere?. If it's only from the farmhouse, and that's not too far away, there may be easier options - such as LoRa

ESP32 with LoRa using Arduino IDE | Random Nerd Tutorials

Learn LoRa basics and how it can be used with the ESP32 for IoT projects using the Arduino IDE. You'll also create a LoRa Sender and LoRa Receiver with RFM95

randomnerdtutorials.com

 

[markuk75]

Thanks for your replay Nigel

So the field is in middle of know where and miles from home.
It's an auto hay feeder for horses.
So yer want to do it of GPRS
I have aprs camera in the field at the moment and that works really well
That got me thinking how I could make the feeder work with gprs.

At the moment it is a set timer running it but but be good to know if it's opened or be able to open it earlyer etc .
Will look in to the links you have sent.

Mark