I have been working on a thermostat based around a MAX31855K ( SEN-13266 ROHS ) and a Red Board Artemis Nano ( DEV-15443 ). When I first assembled the unit it was reading correctly, but when I thought I had mostly finished the project a few days ago the MAX31855K was not reading the correct temperatures. I have tested the sensor on a breadboard with a Red Board Artemis and the same program, and the sample program fallowing the hookup guide with no change to the temperature readings.
Here is the Schematic for the thermostat (it is not perfect as it was made after the board was put together, bad practice I know)
https://tinyurl.com/y6f4jur3
Images
https://photos.app.goo.gl/vrFCDCpJehsXXWHy6
Do you have the same problem when you try the board with an Arduino Uno?
I don’t have an uno, but I do have a Pro Micro C board that I haven’t figured out how to program yet and it doesn’t have headers. I know that it works with the Artemis Nano as it was working while working both on a breadboard and after hooking up the transformer.
Is it possible that a voltage spike could fry the ic?
Is it possible that a voltage spike could fry the ic?
Yes, that’s very possible, over voltage and reverse polarity can also fry the IC.
What are you using for a power supply? Did you purchase the board directly from the SparkFun website?
The power supply is a 12VA 1:10 step down transformer with an LM7805CT regulator.
I put a picture of the power supply board in this album https://photos.app.goo.gl/vrFCDCpJehsXXWHy6
I think what happened was I originally had the diode that protects against back emf backwards, and I bypassed the transistor to energize the relay coil.
That’s what I was thinking. Is there any way to repair the board? Or do I need to just get a new one.
It would be easier and cheaper to just replace the board than to try and fix it.
