04-22-2020 10:29 PM
Hi,
I connect an USB-6000 with Labview 2015, and use channel A1 to measure temperature with a k-type thermal couple.
(Other channels are not connected.)
My room temperature is about 25 ℃, but the value jumps between 55 to -82 ℃.
I've watched the videos about measuring temperature by USB-6008, but there is no similar situation.
I use the same channel to measure the voltage with a battery, and the value is correct. So I think it's not broken.
I think it should be the following possibilities:
1. Incorrect connection
Maybe the USB-6000 cannot connect to k-type thermal-couple directly just like USB-6008.
2. CJC value
I have no idea this value, and the demonstration of USB-6008 didn't change it.
3. Need to filter the data
Maybe there are too much noise.
04-23-2020 12:59 AM
Hi Dodo,
@Dodowang wrote:
I connect an USB-6000 with Labview 2015, and use channel A1 to measure temperature with a k-type thermal couple.
I think it should be the following possibilities:
1. Incorrect connection
Maybe the USB-6000 cannot connect to k-type thermal-couple directly just like USB-6008.
2. CJC value
I have no idea this value, and the demonstration of USB-6008 didn't change it.
3. Need to filter the data
Maybe there are too much noise.
All those cheap USB600x-devices aren't meant to measure thermocouples. Point.
You can try anyway, BUT don't create a DAQmx thermocouple channel! Read the plain voltage signal and convert the voltage to temperature on your own (using the conversion VI found in the Numerics->Conversion palette)! At the same time you should calculate the possible measurement error given all the data in the specsheet of your DAQ device…
1. There is only one way to connect a thermocouple, so the connection should be ok.
2. As said before the cheap USB600x devices don't support thermocouples and provide no CJC channel…
3. Do the same with a simple voltage signal DAQmx channel. It will still show noise, but not as much as in your image (hopefully).