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The higher temperature Isotech Blackbody Fixed Point Cells consist of high purity metals within a graphite body. Graphite reacts with air to form Carbon Dioxide. The rate of the reaction is temperature dependant. The effect is small at low temperatures but increases at higher temperatures.

Primary Standard cells fit into the Medusa and Oberon, covering from Indium to Copper Points. These cylindrical cells are 42mm diameter and have a cavity 9mm diameter x 87mm deep. The Medium Temperature “Hockey Puck” cells are 64mm diameter and fit into the Gemini R. There are a range of High Temperature Cells for the Pegasus, 33mm diameter with a 10mm cavity.

The Isotech Small Hotplate is a lightweight portable calibration system purpose designed for surface mounted sensors. The flat surface plate is made from precision-machined aluminum. The sensor to be tested is simply placed on the surface, for higher accuracy a calibrated surface sensor can be placed alongside and the two compared.

The fundamental problem with surface temperature measurement is that it is subject to large stem conduction errors, also because heat conducted from the surface of the hot-plate causes a localised cold spot to be created which means that the temperature indicated by the hot plate is not necessarily the temperature at the point of measurement.

Isotech produces a miniature resistor with ultra-low temperature coefficient and ultra-high stability. This is achieved because the resistors are oil filled and hermetically sealed.

The Isotech B8 30 130 Cell is small enough to fit into portable Dry Blocks such as the Venus and Europa models. For the larger blocks like the Oceanus Isotech recommend the B12 46 210 with its increased immersion depth.

The most accurately defined temperatures are those defining points (fixed points) of ITS-90.

When we considered low temperature comparison calibration, we had to take into account Health and Safety considerations, both of the liquids used in compressors to generate low temperatures and also the liquids used in the calibration volume itself. The cost of chillers increases considerably for very low temperatures. We concluded that using chillers for very low temperatures was expensive, unsafe and unreliable.

This model is a lower cost alternative to the ITL M 18205. This model is a simple apparatus open to the atmosphere comprising a stainless steel dewar flask filled with liquid Nitrogen, an insulating layer which houses a metallic equalising block and thermometer holder. Lastly a split insulated lid reduces evaporation and permits easy addition of liquid Nitrogen.

Isotech Nitrogen Boiling Point Apparatus is designed specifically to realise and maintain the liquid/vapour equilibrium (boiling point) of nitrogen or argon, for the calibration of thermometers on the International Temperature Scale of 1990.

By temperature controlling an otherwise very stable resistor a performance close to the very best available World-wide can be achieved at a surprisingly low price. The resistor itself is oil filled and hermetically sealed.

This bath is the result of many years of development and is used to maintain the temperature of standard resistors used with thermometry bridges. It can also be used with the Automatic Resistance Bridge Calibrator, A-RBC.