Should you Trust the TrustSens?-Visaya Weekly Episode 38
Hello Visaya, German here! Today is the day a lot of you have been waiting for.
Here we have the self-calibrating temperature sensor from Endress+Hauser, the TrustSens.
If you remember my precision and accuracy video, I told you guys that in order to calibrate your sensor you need a reference measurement that is stable. This means it does not change over time or due to the measurement conditions.
In traditional calibration, oil baths are used to calibrate the temperature sensors at controlled temperatures. The temperature of the bath is precisely controlled and high accuracy sensors are used as a reference to the instrument used in the field.
In contrast, the TrustSens uses a ceramic body as the reference and is placed directly in the sensor.
- How does it work?
- How can a ceramic body act as a reference?
- How do you guaranty that the reference is accurate enough to act as a calibration reference?
Well to explain this I need to explain the Curie Temperature.
At this temperature the properties of magnetic materials change and ferromagnetic materials become paramagnetic.
An example of this is Iron. Iron is the most common ferromagnetic material. If you place a magnet near iron it will be attracted to it.
But if you heat iron to 1043 degrees Kelvin, iron becomes paramagnetic and the magnet will no longer be attracted.
The Curie temperature is a physical property of a material that does not change with time or conditions of the measurement.
The ceramic body used in the TrustSense has a Curie temperature of 118 degrees Celsius. You can compare the temperature measured by the sensor at the same moment as the ceramic body changes its magnetic properties at its Curie Temperature of 118 degrees Celsius.
So what are the benefits of this sensor?
Having a self-calibrating sensor allows you to check the quality of the measurement before each SIP (sterilization in place) cycle. This way you are sure you are not starting your process with a broken sensor. Thusly, taking away any risk.
The TrustSens also has an LED light for on-site verification, red if the sensor is defective and green if it’s working.
The TrustSens comes with HeartBeat technology with diagnostics through HART. Even if you don’t have HART you can use 4…20mA so you can still take advantage of the self-calibrating features.
The TrustSense replaces one part of the custody chain needed for calibration and auditing since the sensor replaces the oil baths used for calibration of the field temperature devices.
So let’s go back to the main question:
Should I trust the TrustSens?
As far as I know, it took 10 years of testing to develop this sensor. After tens if not hundreds of tests they are sure that the reference body is stable and will not change over time.
And there you have it! A high-quality sensor and high-quality reference so you have the complete calibration sensor in one single device.
The TrustSense will launch the next 15.11.2017
Here at Visaya, we love to see how products (even as simple as RTD sensors) continue to evolve. If you have a new device or technology send us an email or leave a comment below. We will happy to share it with our audience.