# MAX6675 thermocouple problem, simplest code:(

Hi I have problem with my MAX6675 thermocouple. I need to have temp in C on serial monitor. But temperature it shows like this:

Deg C = nant Deg F = nan Deg C = 206.25t Deg F = 403.25 Deg C = 206.25t Deg F = 403.25 Deg C = nant Deg F = nan Deg C = 1024.00t Deg F = 1875.20 Deg C = 1024.00t Deg F = 1875.20 Deg C = nant Deg F = nan Deg C = nant Deg F = nan Deg C = 1679.00t Deg F = 3054.20 Deg C = 1706.75t Deg F = 3104.15

It is connected exactly like on this tutorial: http://klinikrobot.com/product/temperature-humidity/max6675-k-thermocouple-module.html

Code :

// Sample Arduino MAX6675 Arduino Sketch

# include "max6675.h"

int ktcSO = 8; int ktcCS = 9; int ktcCLK = 10;

MAX6675 ktc(ktcCLK, ktcCS, ktcSO);

void setup() { Serial.begin(9600); // give the MAX a little time to settle delay(500); }

void loop() { // basic readout test

delay(500); }

Can anyone help me?? or have idea how to fix it?? :confused: I only need to have temp in C on serial monitor, without any other action.

therion: I only need to have temp in C on serial monitor, without any other action.

Then replace the four Serial.print lines with a single tempC line.

or three lines

Serial.print("Temp = "); Serial.print(ktc.readCelsius()); Serial.println( degrees C");

The library seems to print a "nan" if there is no proper reading from the sensor (check connections). Leo..

Connection seems tp be ok, i checked them all.:( Sensor is lying on desk, i dont touch it and it show 1600C, next second 600C then 1024C or nan... its working more like random number generator :( i dont understand:(

Red wire of thermocouple should be connected to + of shield, like on tutorial??

Can anyone try this code?? even with C and Farrenheit scale. I dont care any more about C or F scale i just want to have correct temperature walue

The two thermocouple wires should be connected to the thermocouple terminals and nothing else.

The device reports NAN plus some error codes when you short-circuit it to other terminals such as the +

thermocouple wires are connected to terminal, but terminal have place for wires described + and -. I am using only one terminal, exactly as in tutorial: http://klinikrobot.com/product/temperature-humidity/max6675-k-thermocouple-module.html

You do have to connect both wires the right way around.

i think that they are connnected correctly, i even had try different connections, when connection is bad i have only 0 or nan. when wires are connected properly Arduino allways shows random numbers as temperature.

I had try connect sensor to multimeter and check that it generate few mV when heating, i had stabile signal from 0 to few mV, so sonda is ok.

The probe end of the thermocouple is isolated?