Not sure if I’m in the right place. Please redirect me if not.
I’ve offered to help my grandson with a school project and figured (based
solely on general, overview knowledge) I would use Arduino for the
controller.
We’re going to read the temperature of a cooking pan with a thermocouple
and, when the temperature reaches a certain point (indicating that the water
has boiled away) use Arduino to close a solenoid in the fuel supply line
(propane). Note: We won’t be reactivating the solenoid; it’s just a
one-time shutdown.
millivolts to 70 millivolts.
Besides the main board, what Arduino components do I need to purchase to
accomplish this?
Note: I write software for a living and am fairly conversant with C syntax
so I don’t anticipate much trouble writing the code. However, I don’t know
anything about the Arduino hardware, hence the request for help on what
components I need.
Hi jccviking,
Sounds like a cool project! Here are my thoughts:
- The solenoid cannot be controlled directly by the Arduino, but we do offer these cool I2C controlled relays:
These relays can all handle at least 5 amps at 240 VAC (so they should be able to switch your solenoid easily). It is also super convenient because they use the standardized Qwiic interface (which is based on the I2C bus protocol) so you can plug and play without needing to solder.
-
-8 mV to 70 mV is not a large range… most Arduino boards will have Analog-to-Digital Converters (ADCs) that have a full-scale range of, say, 2V to 5V (most being at 3.3V). So that indicates to me that you will probably want some sort of signal conditioning. You probably don’t need [cold-junction-compensation (recalling from early college labs…) but this [Qwiic Thermocouple Amplifier should make it pretty easy! It works with K-type thermocouples… is that what you have?
-
Since I have recommended some products that use the Qwiic system I would also recommend purchasing an Arduino that has a built in Qwiic connector. If you have already purchased an Arduino that does not have the connector built-in you can use [this adapter. Do you know what style of Arduino you would consider purchasing? There are lots of boards that are all compatible with Arduino and would be programmed in an almost identical way. This application would not need any crazy high performance or special features, but you could purchase one with more room to grow if your grandson (or you yourself) would be interested in doing more projects.
Here are SparkFun Arduino compatible boards with Qwiic connectors from least to most capable:
-
[RedBoard Qwiic - this is our take on the original Arduino Uno with the latest R3 footprint
-
[SAMD51 Thing Plus - this is a powerful microcontroller without any wireless / radio capabilities that uses the Adafruit Feather footprint
-
[ESP32 Thing Plus - this is another Feather footprint Arduino that uses a powerful microcontroller w/ a WiFi / Bluetooth radio built in (one of my favorites)
-
[RedBoard Artemis - this is an R3 footprint board that uses our Artemis module, which is unique for its ability to go into extremely low power sleep - it is also my current project to develop support for (so since it is a WIP I would not recommend as a first-time board)
You may also need some things like the proper USB cable to power the Arduino + the Qwiic relays / thermocouple.
Please feel free to ask if there are any questions.
Hope you enjoy your project!](SparkFun RedBoard Artemis - DEV-15444 - SparkFun Electronics)](https://www.sparkfun.com/products/15663)](https://www.sparkfun.com/products/14713)](SparkFun RedBoard Qwiic - DEV-15123 - SparkFun Electronics)](Qwiic Cable - Breadboard Jumper (4-pin) - PRT-14425 - SparkFun Electronics)](SparkFun Qwiic Thermocouple Amplifier - MCP9600 (PCC Connector) - SEN-16294 - SparkFun Electronics)](Thermocouple - Wikipedia)](https://www.sparkfun.com/products/15102)](https://www.sparkfun.com/products/15093)
Wow! Thank you, thank you! I know I’m in good hands. I will place an order later today.