Incorrect reading from MCP9600 amplifier

Projects General Guidance
1

I am using MCP9600 Amplifier

IMG-20241217-WA0007
IMG-20241217-WA00071600×858 177 KB

I am using the Sparkfun library
The basic reading code is run in Arduino IDE
I don't understand why the readings are incorrect. The thermocouple is exposed to room temperature

2

Please post your sketch using code tags as described in https://forum.arduino.cc/t/how-to-get-the-best-out-of-this-forum/679966#posting-code-and-common-code-problems.

Please post a wiring diagram / schematic diagram reflecting all connections between the Arduino and the amplifier as well as power connections and how the thermocouple is wired. Which (type of) thermocouple?

Which shield / breakout board are you using (link please)?

Note:
The only thing I seem to know about thermocouples is that there are different types and that you can connect them the wrong way around. So I probably can't help you much further.

1 Like
3

Thank you for responding.

#include <SparkFun_MCP9600.h>
MCP9600 tempSensor;

void setup(){
    Serial.begin(115200);
    Wire.begin();
    Wire.setClock(100000);
    tempSensor.begin();       // Uses the default address (0x60) for SparkFun Thermocouple Amplifier
    //tempSensor.begin(0x66); // Default address (0x66) for SparkX Thermocouple Amplifier

    //check if the sensor is connected
    if(tempSensor.isConnected()){
        Serial.println("Device will acknowledge!");
    }
    else {
        Serial.println("Device did not acknowledge! Freezing.");
        while(1); //hang forever
    }

    //check if the Device ID is correct
    if(tempSensor.checkDeviceID()){
        Serial.println("Device ID is correct!");        
    }
    else {
        Serial.println("Device ID is not correct! Freezing.");
        while(1);
    }
}

void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms if available
    if(tempSensor.available()){
        Serial.print("Thermocouple: ");
        Serial.print(tempSensor.getThermocoupleTemp());
        Serial.print(" °C   Ambient: ");
        Serial.print(tempSensor.getAmbientTemp());
        Serial.print(" °C   Temperature Delta: ");
        Serial.print(tempSensor.getTempDelta());
        Serial.print(" °C");
        Serial.println();
        delay(20); //don't hammer too hard on the I2C bus
    }
}

Thermocouple K Type High Temperature Resistance Probe
https://robu.in/product/surface-thermocouple-k-type-high-temperature-resistance-probe/?gad_source=1&gclid=CjwKCAiA34S7BhAtEiwACZzv4UX-lI-FS14lBctVz98k1B99ogHMbAVl4k5ESQD-974cibRro1yL1BoC1GgQAvD_BwE

MCP9600 Amplifier
https://robu.in/product/smartelex-thermocouple-amplifier-mcp9600/

Arduino Uno R3
https://robu.in/product/arduino-uno-r3-ch340g-atmega328p-cable-arduino-uno-transparent-acrylic-case-arduino-uno-r3/

I connected as per the manual (present in the shopping website). I didn't use breadboard.
The power source for my Arduino Board is my Laptop.

wiring
wiring769×706 53.9 KB

4

Your diagram appears incomplete. What else is connected? It seems like you're using the I2C bus for other components, but I don’t see any thermocouple connections. Please provide a complete annotated schematic showing all devices and connections on the I2C bus.