What Is a Psychrometer?

History

According to Institute and Museum of the History of Science, psychrometer means "cold measurer" in Greek and the term was originated by German inventor Ernst Ferdinand August in 1818. Meteorology, Practical and Applied states Sir John Leslie (1776-1832) is to whom we really owe the psychrometer.

Identification

Recognizing a psychrometer is easy once you know what to look for. There will always be two thermometers one or both of which will have a metal extension at the bottom. This is the wet bulb. Instruments for placing in a traditional weather station box will simply have a hole above the thermometers for mounting onto a pivot within the station. A hand held device has a handle, and either a chain connected to some sort of swivel, or the handle will be connected directly to the swivel.

Operation

The "sock" is placed on the bottom end of one thermometer to make the wet bulb. Next the instrument is either swung within the weather box or at arms length for about 30 seconds to reset both thermometers. The sock is then dipped into distilled water until saturated. Swinging the instrument once again for about one minute should allow enough time for the moisture to evaporate. The user will then look at both thermometers and mentally record the readings. Finally it is swung again for about 30 seconds and looked at to see if the wet bulb is still dropping. If the wet bulb has stayed the same both numbers are recorded, if not it is swung for 30 seconds again until the temperatures don't change.

Figure Relative Humidity

Obtaining exact relative humidity and dew-point from a psychrometer requires calculations that can get time consuming without the use of software. The easiest route to glean this information is through the use of a psychometric chart. These can be purchased, often with your psychrometer, or one can be downloaded from the Internet. Generally these charts require you to find both of your readings on the chart and match them up to the corresponding relative humidity. Dew point temperatures can also be found on these charts.

Warning Resources More Like This

Facts About Psychrometers

How to Make a Homemade Psychrometer

How to Read a Sling Psychrometer

You May Also Like

Roundworms are invasive parasites that can infect pets and even people if caution is not taken. A healthy, clean environment is the.

Weather forecasters, meteorologists and other scientists use a variety of instruments to measure data. The data is then analyzed, compared to existing.

Types of Old-Fashioned Weather Instruments. Greek philosophers Aristotle and his pupil Theophrastus showed interest in weather phenomena more than three centuries.

The amount of moisture in the air, known as humidity, is an important component of the weather, measured by meteorologists and homeowners.

A hygrometer is an instrument used to measure humidity, the amount of water vapor in the air. The earliest form, the mechanical.

A sling psychrometer is a device used to measure the relative humidity, or amount of moisture in the air. A psychrometer is.

Since most of us have watched the news from time to time, we',re more than familiar with newscasters and meteorologists giving us.

Asbestos is the name given to a group of naturally mined fibrous silicates. Its is an extremely effective thermal and acoustic insulator.

A sling psychrometer is an instrument that measures the relative humidity and dew point in an area. A sling psychrometer has two.

A hygrometer is a meteorological instrument that measures relative humidity. Relative humidity is a ratio of the partial pressure of water vapor.

No one knows for certain where and when the first jack-in-the-box toy was made, but the toy can be reliably traced back.

Source