Arduino Uno R4 WiFi Temperature Sensor with Text and Email Alarm

[@michellesullivan1594]

Genius!!

[@nealcameron9201]

Great idea and way to handle the problem. Just wondering what happens if the temperature drop is due to a weather related power drop and wireless access point is lost at location being monitored? Maybe a battery backup and cell service provided internet with a sensor that lets you know it’s a power failure. Just a thought. I know you can’t cover every angle.

[@_EasyOnEasy_]

Cool build! The Seeed ESP32C3 it a $5 microcontroller that could probably do a similar thing in a smaller footprint.

[@adsullivan406]

Thanks for the suggestion. The ESP32 is something I learned about for the first time using the Uno R4 in this project. I think I am going to try it out for one of my next projects.

[@eideticgoone7035]

I'm no expert, but I would think using a sensor with an integrated digital interface would avoid all the calibration and resistor offset issues. One I am thinking of using in a project is the DS18B20 based Temperature Sensor. They come in a waterproof package and are pretty inexpensive at 5pc for $11 on amazon. This is supposedly accurate to 0.5C between -55 ℃ ~ +125 ℃ and uses 3 wires to power and interface to the Arduino with the one-wire serial interface and requires only a 4.7k pull up resistor.

[@adsullivan406]

Agreed and thanks for the input. The TMP36G has an accuracy of 3°C (5.4°F) per the datasheet. The two I tested were right at this limit reading higher than actual based on my other thermostat and a Fluke 52 temperature sensor. 5°F is enough that you can tell it isn’t reading right based on what the room feels like, so a little calibration made sense. The MAX31820 datasheet reports a ±0.5°C which would eliminate the need for calibration. Both sensors are cost effective.

[@CentralVaWoodturners]

I'm getting a crash after two successful emailings. #### Error, fail to set up the SSL/TLS structure ! E: fail to set up the SSL/TLS structure Connection error, Status Code: 220, Error Code: -402, Reason: fail to set up the SSL/TLS structure Suggestions?

[@mcdermid85]

Long time no talk sir...tried calling ya a while back. How have you been?