Wifi, thermocouples, touchscreen

Projects General Guidance
1

I'm working on v 2.0 of a project which reads 2 thermocouples and sends the results to a Raspberry Pi. It works well enough but it's built on a breadboard and is quite unwieldy.

My primary goal is to shrink the project down by getting rid of the breadboard & Raspberry Pi. This means I'll need to display the temperature on the 2.8 inch touchscreen I already have, connect the thermocouples with a shield which will handle the small signal from them, and add a wifi board.

  1. Is it reasonable to try to put all of this into a smaller footprint given the current ability to stack & interface different boards with one another?

  2. Is a board available to read the thermocouples without having to amplify the signal beforehand?

Thanks!

2
  1. Yes.
  2. I have forgotten the outpur range of thermocouplers... Tell me that, and the resolution You need. Arduinos read analog signals of the range 0..5 volts or 0...3,3 volt depending on Vcc, using 10 bits, 1024 steps.
3

Thanks for your reply, Railroader.

This is the Type-K thermocouple I'm using: Thermocouple Type-K Glass Braid Insulated [K] : ID 270 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits

In the previous version of this project I used the MAX31855 breakout board for the thermocouple connection.

4

Thermocouple puts out about 35millivolts. check the full span of your ADC input.

there are more reasons to use a chip to read a thermocouple.
the first is the cold junction you want to read the end where two different metals join.
the goal is that THAT point is at your target and not at the screw terminal on your input.

Also you should be able to get relatively small devices to nest into one enclosure.