From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.
We appreciate your patience as we improve our online experience.
We have an NI9213 reading 2 k-type thermocouple voltages in Labview. However, they seem to be reading voltages corresponding to temperatures about 20 C lower than intended (tested in ice water, at room temperature and in boiling water.) Multiple k-type thermocouples were tested using varying lengths of shielded thermocouple wire between the leads and the 9213. Is it possible that there is a voltage offset in the module? I would appreciate any suggestions on ways to fix this.
How are you configuring your thermocouple task in LabVIEW? Make sure that you specify the right type of thermocouple in LabVIEW if you are using a K-Type thermocouple. In addition if you do not have the correct CJC source you could be getting this offset. There are several useful examples in the NI Example Finder that may help you configure your thermocouple task. The example finder can be found under Help>>Find Examples and the thermocouple VIs can be found under Hardware Input and Output>>DAQmx>>Analog Measurements>>Temperature. Another useful tool that may be helpful for your application is Measurement & Automation Explorer. You can use this to configure your hardware and set up a temperature task. This will help you isolate whether the issue is occurring in the hardware or software setup.
We had it set as a voltage, not temperature since we were hoping to read in a data table instead of using the linear fit for mV to degrees conversion. However, upon changing it to the temperture type, it seems to be working properly.
