Case Study – Accurate Verification of Short Temperature Sensors

A manufacturer of animal health products, needed to verify their sensors in ultra-low temperature freezers.  The customer had problems verifying short sensors from 6 to 8 cm in length, in the 0°C to 90°C range.  They could not get the sensors to match the temperature that was indicated on the temperature calibrator they were using.  This was because the short length of the sensors did not allow it to be placed in the ideal location of the temperature calibrator.

The RTC156 from Jofra was demonstrated and the function of the unique dual-zone heating feature was explained.  This feature provides a uniform temperature throughout the entire dry block, making it perfect to calibrate these short sensors.

Also explained was how the customer could insert the STS-102 reference sensor at the same depth as the tip of the sensor under test.  This provides an exact comparison of the two sensors – thereby eliminating the temperature error they were experiencing by using their old method.

 

Reduce the calibration error by 3°C

The RTC solution was tested, and the result was an improvement of 3°C at 54°C.  The original device read the same temperature as 51°C, while the RTC solution removed this 3°C error and correctly displayed 54°C.

The same solution has also been used at a carrot processing plant that takes full sized carrots and turns them to shaved baby carrots, and juice.  They had many sanitary temperature sensors they needed to verify.  Even though the product was different, the application was the same – short sensors that need to be verified correctly.

AMETEK Solutions

Ametek offers a complete, highly accurate, and portable calibration solution, by combining a small reference sensor, which is placed in parallel with the sanitary or short sensor, and the RTC dry block featuring the dual-zone technology.

Their sanitary sensor calibration kit has been designed for their calibrators and works perfectly with the RTC-156.  The customized inserts and short reference sensors have been developed specifically for these applications.

Written by:  Ametek Test & Calibration