A New Dry Block
The Isis 525, a high-accuracy Isotech dry block calibrator, offers operation to temperatures as low as -100°C, and is the first dry block working to such low temperatures. Now it is possible to calibrate temperature sensors such as PRTs, Thermocouples and Thermisters at ultra low temperatures without the need for a liquid bath.

Portability and Safety
Unlike a liquid bath, the Isis requires no costly or hazardous fluids, and offers great portability. This will be of particular value to calibration engineers working on site with low temperature freezers, as encountered in pharmaceutical, aeronautical and food environments.

The minimum operating temperature is lower than stirred liquid laboratory calibration baths, and users in laboratories will also benefit by avoiding the ongoing need for expensive fluids.

The maximum operating temperature for this Isotech dry block calibrator is 40°C, a little higher than the minimum operating temperature of Isotech Hot Blocks. This permits covering the range from -100°C to 650°C or higher with just two Isotech blocks. By limiting the maximum temperature, the reliability and operating life of the cooling engine is maximized, and has been agreed in consultation with the licensee of the cooling technology.

Cooling Technology
The Isis makes use of a Free Piston Stirling Cooler (FPSC), which provides a massive 80 Watts of cooling power to the calibration block. Specialist materials, patent applied for, are used for the heat transfer from the FPSC to the block.