Radio Frequency Interference and Thermocouples

[jab10015]

Hello NI Community,

I am new to the forum and have been struggling with a problem regarding radio frequency interference (RFI) and K type thermocouple sensors. In my situation, I am measuring the temperature of a material and saline in a particular environment using thermocouples. The environment has a great deal of radio frequency energy running through it due to the use of a radio frequency electrode probe (RFE probe). This probe is often used in surgery and emits energy in the range of 300-400 kHz, The thermocouples relay temperature readings first through a NI-9216 16 channel thermocouple system and then to a LabView program. When the probe is not in use, our temperature readings are accurate and completely fine. When the probe is being used, however, our reading is skewed and all that is shown is a great deal of noise. I know that this is caused by RFI, however, I am confused on how to go about solving this problem. I could create a low-pass filter on a breadboard for the positive and negative leads of the thermocouple sensor and then proceed to connect them. I have also found radio frequency thermocouples, which are said to shield the thermocouple from this type of interference. Shielded thermocouples are also a possibility, however, I have heard from an electrical engineering professional that these would not completely solve our problem. What do you all think would be the best possible solution for my problem? Thank you for the help.

[Dennis_Knutson]

This board is for an obsolete product called Measure - an add on for excel. You should post to a more appropriate board or ask the moderator to move it (click on Options).