Reduce calibration effort and risk in CIP processes

Cleaning in Place (CIP) processes require reliable temperature monitoring to ensure hygienic conditions and consistent product quality. iTHERM TrustSens enables inline self-calibration during CIP cycles, reducing manual calibration effort and avoiding production downtime, while providing traceable, audit-ready documentation and significantly lowering the risk of undetected sensor drift.

iTHERM TrustSens by Endress+Hauser introduces a fundamentally different approach to calibration in CIP applications. By integrating the thermometer, operators achieve higher reliability in temperature measurement, as inline self-calibration during regular cleaning cycles allows frequent validation of accuracy compared to traditional periodic calibration. Continuous verification during operation reduces the risk of undetected sensor drift and allows longer calibration intervals without compromising compliance.

Temperature sensors installed at critical control points (CCPs) must deliver accurate and reliable measurements at all times to ensure effective CIP cleaning and regulatory compliance. Conventional calibration concepts typically require removing the sensor from the process and interrupting production, resulting in increased maintenance effort, downtime, and cost. In addition, sensor drift may remain undetected between two calibration intervals, posing a potential risk to product quality and process safety.

CIP processes consist of multiple steps, including hot caustic and acidic cleaning phases followed by cold-water flush out steps:

These phases are characterized by rapid and recurring temperature changes, particularly in the CIP return line, caused by alternating hot cleaning media and cold rinsing phases. Monitoring the correct cleaning temperature at this point is essential to ensure that residues are reliably removed throughout the entire system.

• Measuring point of tempera­ture sensors: in the return line
• Process temperatures: 20 to 70 °C (68 to 158 °F)
• Rapid temperature changes during rinsing and cooling phases
• Frequent repetition of CIP cycles depending on produc­tion schedules

iTHERM TrustSens TM371 (metric) or TM372 (imperial) is specifically designed to address these challenges in hygienic and regulated applications. The device does not only compare two values but uses a physical fixed point reference sensor based on the Curie effect.

For CIP applications, the low-temperature calibration point at 39 °C (102 °F) is used, which lies within the typical temperature window of CIP processes. The temperature drop during the rinsing phases is the most frequent recurring condition in CIP processes. Self‑calibration is triggered when the temperature passes the calibration point and the process follows the temperature profile described in the Technical Information and shown in the figure below.