Hart PRT Probes Perform In Extreme Environments

Fluke's Hart Scientific Division has brought out the 5606 and 5607 full immersion platinum resistance thermometer (PRT) probes, which are designed to perform in extreme environments. The Hart PRTs perform in applications where both the transition junction and the lead wires must withstand temperatures covering the entire operating range of the probe. Such applications can include calibration or validation of sensors used in laboratory or bio freezers, walk-in refrigerators, autoclaves, ovens, stability test chambers, furnaces or incubators.

The Hart Scientific 5606 has a temperature range of -200C to +160C, while the 5607 has a range of 0C to +450C. The 5606 is only 2in (50mm) in length with a sheath diameter of 1/8in (3.1mm). Since it can be fully immersed over its entire temperature range, users need not worry about calculating minimum immersion depth and can immerse the entire probe, transition junction and lead wires in either non-corrosive liquids or dry mediums.

The lead wires of the 5606 are made of single-conductor enamelled copper wire, which prevents moisture from wicking to the sensing element as it would if a more common, stranded lead wire was used. The diameter of the lead wire is no greater than 0.2mm, making it easy to run lead wires through a freezer door to a readout or transmitter with effectively zero energy loss. The 5606 has been proven in common heat-transfer fluids such as silicone oil, mineral oil, ethanol, and even liquid nitrogen with no degradation of the transition junction seal or lead wire insulation.

The 5607 performs calibrations or verifies the accuracy of sensors used in ovens or furnaces. Intended to be used in dry mediums, the 5607 can be fully immersed in dry mediums over a temperature range of 0C to +450C. The lead wire of the 5607 is shielded with braided stainless steel and connected to the transition junction with a strain-relief spring. The Hart Scientific 5606 full immersion PRT has a list price of USD385 (GBP237), the 5607 has a list price of USD465 (GBP287).

Insertion Probes Monitor Bioproduction Process

Stratophase has collaborated with the Centre for Process Innovation (CPI) to develop an insertion probe variant of its Spectrosens system. Enabling real-time monitoring of the bioproduction fermentation process, the multi-output Spectrosens insertion probes track compositional changes and monitor temperature in the liquid.

Multiple discrete readings can be taken simultaneously at numerous locations, providing more reliable measurements and a reduced chance of false positives. As a result, the entire fermentation process can be precisely monitored to ensure reproducibility and clear determination of the desired end-point. The Spectrosens system sensors can be placed throughout the production process and networked via the control and analysis unit.

Using only light at the point of measurement, the sensors are intrinsically safe and spark free, removing any chances of ignition. The insertion probe fits standard ports for dissolved oxygen (DO) and pH probes, enabling ultra-high resolution, optical microchip technology to be applied to existing benchtop and large-scale bioreactor equipment. Other tried and tested applications of the Spectrosens insertion probe include biofuel production and sustainable polymer development. The probe system is currently being trialled at the UK's National Industrial Biotechnology Facility (NIBF).