The S8000RS from Michell Instruments is a compact chilled mirror hygrometer which measures dew points down to -90°C with no external cooling.
The hygrometer is designed to fit into a standard 19-inch rack and doesn’t need extra equipment to work.
Its compact design was possible due to a new optical system that detects very small changes in moisture condensed on the mirror surface.
This ensures high sensitivity and fast response when measuring low dew points.
Although referred to as ‘dew-point temperature’, chilled mirror hygrometers most often measure the frost point because the temperatures are below freezing.
However, in some conditions, liquid water can exist as ‘super-cooled water’ in temperatures as low as -40°C.
As the difference in condensing temperature between water and ice can be as much as 10 per cent of the reading, it’s important to know which phase you are measuring.
The S8000RS uses Frost Assurance Technology (FAsT) to ensure ice, not liquid water, is present on the mirror surface at low temperatures so measurements are always a known quantity.
The S8000RS is available from AMS Instrumentation & Calibration.
