How to remove hysteresis from a temperature sensor

[Topher925]

I'm having an issue with an RTD in the lab that I think may have some hysteresis affects going on with it. I know RTDs can be prone to this if not used properly but is there any practical way to confirm this without using some other standard (The RTD is the most accurate temp sensor I have available)? I was thinking of putting the sensor in a water bath and then ramping the temp up and down a few times while recording the results in set time increments to see what would happen. Is there any other way of doing this while not going below room temp?

 

[Bob S]

I think the problem with the RTD (resistance temperature detector) may be a delay in the correct reading due to the specific heat of the sensor or the water bath. Ramp up the temperature to a fixed value, and wait for the RTD to catch up. Simultaneously measure the water temperature with another thermometer.

 

[oswaler]

Hysteresis is a common issue with temperature sensors, especially RTDs, and it can significantly affect the accuracy of your measurements. Fortunately, there are some practical ways to remove hysteresis from a temperature sensor.

One approach, as you mentioned, is to perform a temperature cycling test in a controlled environment, such as a water bath. This will help you understand the hysteresis behavior of your sensor and determine the extent to which it is affecting your measurements. However, it is important to ensure that the temperature cycling is done gradually and consistently, as sudden changes in temperature can also introduce error.

Another method is to use a reference standard, such as a calibrated thermometer, to compare the readings of your temperature sensor. This will help you identify any discrepancies and determine if hysteresis is indeed the issue.

Additionally, it is important to ensure that your temperature sensor is being used and maintained correctly. RTDs are sensitive to factors such as vibration and electrical interference, so make sure to follow proper installation and handling procedures.

In some cases, hysteresis can also be reduced by implementing a compensation technique, such as using a software algorithm to adjust the readings based on the sensor's hysteresis behavior.

Overall, it is important to carefully monitor and understand the hysteresis behavior of your temperature sensor to ensure accurate and reliable measurements. By following these steps, you should be able to effectively remove hysteresis from your sensor and improve the accuracy of your results.