Hello, I'm using MAX31855 tipe K for measuring temperature. I can get right value if the TC wire is short only, for example 30 cm in my case. I start getting wrong measurement if I use long wire, for example 4 meters. What do I do wrong? Thank you.
The uncalibrated accuracy on the MAX31855 should around +-2degC. The repeatability should be a bit better. When I did a quick test nn my new board I was getting +-2degC and a repeatability of around +-0.25degC. I will doing some tests over the next few weeks.I added two channels to the board and some terminal blocks for ADC channels, I2C and SPIports. I also added a 5V boost converter.I will have the schematic and documentation done in the next few weeks.Preliminary information is at http://tinyurl.com/3vuatby(* jcl *)