MAX31865 is giving fault code RTD Low Threshold

[the_Elders]

Good evening,

I purchased Adafruit METRO M0 Express, the MAX31865, and the PT100 3-wire sensor. I followed this guide to set things up:

https://cdn-learn.adafruit.com/download ... lifier.pdf

The guide says to solder the jumper labeled 2/3, cut the wire connecting the left side of the 2 way jumper, and solder the right side just above the Rref which I did. I am monitoring the COM port and am getting the error Fault 0x40 which is "RTD Low Threshold".

My theory is because I attached the METRO M0 5V to the MAX31865 that the MAX31865 was killed (even though the board says it can take up to 5V). I should have just started with the 3V pin instead but I wasn't thinking.

Here are 3 pictures of the project.


Any help is greatly appreciated.

[mikeysklar]

Please go over the pin soldering again. There are cold joints on the MAX31865 showing little to no solder flow to the pins.

[the_Elders]

So i resoldered some of the joints and ultimately that fixed my problem.

Along the way I "bricked" the Metro Express M0 and started getting the error message from Windows 10 "device descriptor request failed".

Luckily I had a spare Arduino Uno sitting around so I plugged that in and got the system working in about 30 seconds.

Thank you for taking the time to look at my pictures and poor soldering work :)