AMS Instrumentation and Calibration introduces the new and improved Optidew chilled mirror hygrometers from Michell.
Designed to exceed the specifications set out in the Code of Federal Regulations (CFR) for Engine Testing, an essential requirement for any instrument used for emissions testing in the US and many other regions, the new industrial chilled mirror hygrometer combines the accuracy and integrity of a laboratory hygrometer with the robustness to survive in a tough industrial environment.
The CFR code sets out a number of criteria for humidity measurement instruments, all of which have been met and exceeded by Michell’s Optidew hygrometer:
The Optidew has an accuracy of ±0.2°C, twice better than the required dew-point accuracy of ±0.5°C.
The Optidew has a repeatability of 0.1°C, five times better than the required repeatability of 0.5°C.
The Optidew updates its digital outputs every 5 seconds, or 0.2Hz twice as frequent as the required data update frequency of 0.1Hz, or once every 10 seconds.
The Optidew consistently has less than 0.008°C noise on its outputs. The maximum output noise level is 0.02°C.
The complete system rise and fall time, which is the time taken for the sensor to heat or cool from 10% to 90% of its range, should be no more than 50 seconds – the Optidew has a total rise/fall time of less than 45 seconds.
Michell’s industrial chilled mirror hygrometers feature a rugged 316 stainless steel NEMA 4/ IP66 wall mount enclosure suitable for installation in an engine test room, while the remote sensor can be mounted directly into the engine air-intake ducting.
The Optidew gives reliable results every time because it measures a primary characteristic of moisture – the temperature at which condensation forms on a surface. With no calculated variables that can shift over time, the Optidew is ideal for monitoring engine test cell inlet air where consistency of measurements and long-term reliability are vital.
All vehicles with petrol or diesel engines require emissions testing with engine tests ensuring that their emissions meet the current standards to protect the environment and prevent pollution. While the exhaust gases are typically checked for concentrations of carbon monoxide, hydrocarbons, nitrogen oxides, formaldehyde and particulate matter, precise measurements of the humidity and temperature of the air in the engine intake is vital for the accuracy of the tests.