Hi,
I am a complete beginner with Arduino Uno.
In my project I have a heat exchanger with microchannels. I need to measure the liquid temperature of inlet and outlet and also the pressure drop. I want to use Arduino uno, I found some links showing the use of Arduino with Ambient temperature sensors. However, the sensor is different from mine (My sensor has 2 probes for ground and output and one probe for reading the temperature.) My pressure sensor is a differential pressure sensor with 4 pins.
I'd be thankful if you share with me some ideas on how to start using the Arduino uno with these kind of sensors.
Thanks!
Leily
If you have a link to a datasheet for your heat exchanger it would make it much more likely for you to get useful help.
leilymjd:
My sensor has 2 probes for ground and output and one probe for reading the temperature.
That might indicate it's not just a standard thermocouple because they only have 2 wires but I'm using the Adafruit MAX31855K breakout board to read type K thermocouple with Arduino. They have a tutorial, library, and example sketch for it. I actually prefer Rob Tillaart's MAX31855 library because of the way it returns error codes but either library will work fine.
As for the pressure sensor you will have to find the part number or provide more information because there are many different types of pressure sensors.
Do you have a link to the sensor specs. A bare Type-K thermocouple may require some additional electronics to boost the millivolt output to something in the 1V ballpark.
Then if I remember how thermocouples work, you'll have to calibrate the non-linear voltage output to a linear temperature reading.
Where I work, we have a device that uses an [u]AD594[/u] chip to amplify the signal, and it also provides a "cold side" temperature reference.
I don't know the details of how it works, but I assume the linearization is done in software. We do calibrate the accuracy/readings in software. Before calibration it can be off by several degrees. And, we don't actually calibrate it with temperature.... We have an instrument that simulates the measurement-side thermocouple that we can set between -200 and +400 degrees Centigrade. And, I'm not sure where the error comes from... It's either the AD594 or the DAC.
It's a rather old design, and I assume if it was designed today we'd just use an LM34 or LM35 temperature sensor.
You might use the forum search in the upper right of this page as there have been previous post concerning use of thermocouples for BBQ grills and such.
DVDdoug:
Where I work, we have a device that uses an [u]AD594[/u]
AD594 is for type J thermocouple, AD595 is made for type K.