The 115-01 is a laboratory grade thermo-hygrometer for accurately measuring indoor and outdoor conditions.
The stainless steel housing is vented for fast and accurate readings when mounted inside our outside in a shaded, protected area.
The hygrometer includes a set screw for calibrating the humidity.
A spirit thermometer is available for accurately measuring the temperature.
Includes mounting hook for easy mounting.
Note: The 115-01 has a non-linear hygrometer scale, providing larger graduations at lower humidity readings. Order the 125-01 for the linear-graduated hygrometer.
Background: This instrument measures the relative humidity of the atmosphere with high precision (These are 3%, to get to 1% costs more than $1,500). Relative humidity is a crucial factor in weather analysis and forecasting and human comfort. The data are also crucial to the safe storage of many products and instruments.
This purely mechanical instrument has been a prized product of the Fischer Precision Instrument Company for more than 60 years. It has no electronic components. The sensor element is a specially treated synthetic fiber whose length is sensitive to the humidity in the air. For a given tension on the fiber bundle, the length increases with increasing relative humidity. Changes in its length are then magnified with precision gears to display the relative humidity of the air.
Installation: Relative humidity is closely correlated to and dependent upon air temperature, so it provides best data when not exposed to rapidly changing temperatures. For the best measure of the humidity, avoid placing the instrument in direct sunlight or in line with strong breezes. Locate the instrument in a place that best represents the average temperature of the local environment. Avoid outside walls that might be cooler than average, and avoid direct exposure to heat sources that would be warmer than average.
Healthy room environment: It is often considered that 40% to 60% is a healthy and comfortable relative humidity range, and with a hygrometer showing the actual value you may find that added moisture in the winter would be beneficial.
About Fischer Instruments...:
The Fischer factory for precision instruments was founded in 1945 by aircraft engineer Kurt Fischer, in a small village in the Erzgebirge called Drebach.
Still owned and operated by the Fischer family, the experienced engineers and craftsman have designed quality instruments for measuring weather and climate.
Precise instruments, well balanced, and well crafted to the finest detail.
Distributed exclusively in the USA by Ambient Weather, this piece includes a two year warranty.