Pmod TC1 reads too high temperature

[dougBe38]

I have two Pmod TC1 that I use with an Ardunio Mega. They both return too high temperature. One reads 30.5°C and the other 28.5°C when it should be about 22°C. I moved the termocouple to a calibrated thermometer and got 22°C. When I start (or restart) the Arduino the temperature starts at about 26°C and increases up to 30.5°C and 28.5°C after a few seconds.

What could be the reason?

[JColvin]

Hi @dougBe38,

Could you attach the code that you are using to read the Pmod TC1?

Additionally, are you using any sort of voltage translator while working with the Pmod TC1? The embedded chip on the Pmod TC1 only accepts voltages from 3V to 3.6V and from my understanding the Arduino MEGA only uses 5V logic, so that would change the operating specifications.

Thank you,
JColvin

[dougBe38]

// Pins for tempmodule #1
#define CS 10
#define MISO 12
#define SCLK 13

// Pins for tempmodule #2
#define CS2 4
#define MISO2 6
#define SCLK2 7

#include <SPI.h>
#include "Adafruit_MAX31855.h"

Adafruit_MAX31855 Temp(SCLK, CS, MISO);
Adafruit_MAX31855 Temp2(SCLK2, CS2, MISO2);

double T1;
double T2;

T1 = Temp.readCelsius();
T2 = Temp2.readCelsius();

I power the Pmod TC1s with 3.3V, but no, I do not use any voltage translator.

[dougBe38]

18 hours ago, JColvin said:

Hi @dougBe38,

Could you attach the code that you are using to read the Pmod TC1?

Additionally, are you using any sort of voltage translator while working with the Pmod TC1? The embedded chip on the Pmod TC1 only accepts voltages from 3V to 3.6V and from my understanding the Arduino MEGA only uses 5V logic, so that would change the operating specifications.

Thank you,
JColvin

A voltage translator seems to have done the trick. Now the temperature is within spec. About 0.5-1°C above my calibrated reference. Thank you!

[jpeyron]

Hi @dougBe38,

Glad to hear your Pmod TC1 project is working correctly. Thank you for sharting what you did to fix the issue.

cheers,

Jon