Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
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Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
can anybody help with the sketch for interfacing the RGB LCD shield with the MAX 31855 amplifier to get thermocouple readings using a stand alone arduino uno.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
What help do you need? Post your current sketch and describe what it does or doesn't do for you.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
I was just using the example for the max 31855 to get the thermocoulple reading and was getting weird results of like 6 degrees and -200 while I'm at a room temperature of about 24.
is something wrong with the library or is their something i need to change?
Code: Select all
#include "Adafruit_MAX31855.h"
int thermoDO = 3;
int thermoCS = 4;
int thermoCLK = 5;
Adafruit_MAX31855 thermocouple(thermoCLK, thermoCS, thermoDO);
void setup() {
Serial.begin(9600);
Serial.println("MAX31855 test");
// wait for MAX chip to stabilize
delay(500);
}
void loop() {
// basic readout test, just print the current temp
Serial.print("Internal Temp = ");
Serial.println(thermocouple.readInternal());
double c = thermocouple.readCelsius();
if (isnan(c)) {
Serial.println("Something wrong with thermocouple!");
} else {
Serial.print("C = ");
Serial.println(c);
}
//Serial.print("F = ");
//Serial.println(thermocouple.readFarenheit());
delay(1000);
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
The thermocouple amplifier is very sensitive and the readings can be affected by electrical noise. Keep the thermocouple probe away from other wiring and use the shortest wire possible.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
Looks like there was a bug in the 31855 library.
Delete the old version and download the new version. See if that helps.
Delete the old version and download the new version. See if that helps.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
That affected readings below 0C (32F)Looks like there was a bug in the 31855 library.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
Hello,
I'm getting very similar results to the OP. -2000 deg C, to about 10 deg C at room temperature. It seems like it's discontinuous between -2000 to 6 deg C, switching back and forth rapidly. Was there ever a resolution to the problem?
Scirocco
I'm getting very similar results to the OP. -2000 deg C, to about 10 deg C at room temperature. It seems like it's discontinuous between -2000 to 6 deg C, switching back and forth rapidly. Was there ever a resolution to the problem?
Scirocco
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
The amp is very sensitive to noise, which can result in unstable readings. You can try putting a 0.1uF or 0.01uF capacitor in parallel with the thermocouple probe in the screw-terminal block to tame the noise.
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Re: Interfacing the NEG RGB LCD to display thermocouple readings from MAX 31855
make sure to download the latest library - we had a few bugs with negative temp readings. delete the old library completelyScirocco wrote:Hello,
I'm getting very similar results to the OP. -2000 deg C, to about 10 deg C at room temperature. It seems like it's discontinuous between -2000 to 6 deg C, switching back and forth rapidly. Was there ever a resolution to the problem?
Scirocco
Please be positive and constructive with your questions and comments.