Endress+Hauser’s iTHERM Self-Calibrating Thermometers Create New Possibilities with Additional Smart, Safety, Features
June 29, 2023
Endress+Hauser has introduced generation 2.0 of its iTHERM TrustSens TM371/TH372, which they claim is still the world’s only self-calibrating RTD thermometer for hygienic operations.
Gen 2.0 includes new smart and safe features for added convenience and expanded roles in the life sciences and food-and-beverage sectors in particular. These include a wider operating temperature range (-40 to 190ºC), explosion protection, optional Bluetooth/WirelessHeart connectivity and potential integration with Netilion, Endress+Hauser’s cloud-based IIoT ecosystem.
The added explosion protection and expanded temperature range (up to 160°C as standard and 190°C as an option) creates potential new applications for iTHERM, including monitoring of edible oils and UHT milk or baking and frying processes. Certification for Ex-ia/IS makes it suitable for dust and gas applications like storage of grains, flour or pet food or for monitoring production of milk powder and alcohol or for sterile filling or ethylene oxide sterilization.
Adding Bluetooth or Wireless/HART connectivity can provide easy access to calibration data and device configuration parameters in the field, without the need to unplug or dismount the device. It means faster access to the device diagnostic and process data generated by the device’s Heartbeat Technology for optimizing processes and overall plant performance.
Considering that some production facilities can have hundreds of thermometers, often in hard-to-reach places, the time and cost benefits of being able to access this data on a smartphone or tablet from a safe distance are obvious. With Netilion integration, such monitoring can be done centrally, even remotely, 24/7.
The iTHERM TrustSens TM372 (imperial style) and its metric equivalent, TM371, enables continuous, traceable monitoring thanks to their fully automated inline self-calibration function without process interruption. This results in high product safety, increased plant availability and reduced risk and costs. It is ideal for users who require absolute compliance with FDA and/or GMP regulations.
The genius of the iTHERM TrustSens technology and why it’s won over so many customers is the sensor unit, consisting of a primary Pt100 temperature sensor and a highly accurate integrated reference with long-term stability. The reference sensor uses a physical fixed point on the basis of the Curie temperature and therefore serves to regularly calibrate the primary sensor.
The self-calibration is triggered fully automatically at a temperature of 118°C (Curie point of the integrated reference), a process typically occurring during steam sterilization (SIP) cycles at a plant. This ensures that the constantly high measuring accuracy of the temperature sensor is permanently monitored throughout its entire life cycle. The iTHERM TrustSens has a <0.35 K (excellent) to <0.55 K (standard) calibration uncertainly compared to manual calibration, which can have an uncertainty factor up to ±1 K, especially if the task is performed by inexperienced personnel or under suboptimal conditions.
The iTHERM TrustSens provides audit-compliant calibration data for complete documentation at all times: A valid calibration certificate can be produced automatically with a simple mouse click (eg. with the Endress+Hauser FieldCare software). Moreover, verification of the thermometer’s measuring accuracy data from the last 350 calibrations is stored directly in the device (FIFO memory). This makes it possible to access a long device and process history, which can be used as a basis for predictions and the early determination of trends. As such, the iTHERM TrustSens is Industry 4.0-ready and future-proofed.
