ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel


Updated on May 20, 2013

Psychrometer | Simplest instrument to measure relative humidity level

Looking for an instrument for measuring relative humidity level? The most common humidity level measurement instrument is hygrometer, of all kinds of hygrometer, psychrometer is the simplest instrument.

Commonly used in laboratories to monitor humidity around the lab, psychrometer is very important as the researches require certain level of humidity to meet the procedure.

There are some forms of psychrometer which are available nowadays: sling psychrometer and digital psychrometer.

Who uses Psychrometer?

Besides the laboratory use, psychrometer is an instrument every meteorologist should be able to use - to predict the weather.

In America, the country of twister and tornado, this instrument is very important to predict incoming hurricane as they come with the sign of significant temperature and humidity changes.

For this reason, storm chasers put this instrument as a must-have instrument too.

It can also be used to decide a place for storage as some products, food or materials are very sensitive to certain humidity. That case, we can be ensured that we will no longer have to throw our home appliances, food or clothes due to molds.

Sling Psychrometer

The most popular Psychrometer is sling psychrometer.

Some people know this instrument as a wet and dry-bulb thermometer as it consists of two similar thermometers which are mounted together with a lever attached on a string.

The dry bulb is an ordinary thermometer which is exposed to air to measure the normal temperature of the environment. The wet bulb thermometer is wrapped in a cloth wick. The cloth used is usually an absorbent material such as cotton.

This instrument got the name of sling psychrometer because it is placed on a structure that can be spun around up in the air.

Before it is used, the absorbent cover of the wet bulb is soaked in water. Once it is taken out of the water, the psychrometer will be spun around to hasten evaporation. The evaporation of the water will cool the wet bulb. In this phase, the humidity of the atmosphere around will make account to the amount of evaporation and consequent cooling of the thermometer as it depends to it. Water is evaporated faster in drier atmosphere.

Evaporation is slow in area with high level humidity.

The air's ability to absorb humidity is measured by the wet-bulb thermometer. One the meantime, the dry-bulb one measures the normal temperature of the area. The psychrometer is usually spun about a minute. It is enough to measure the difference in the between two thermometer. The temperature shown by the wet-bulb thermometer is quickly read and recorded before the dry one as it will be changed quickly.

The instrument can be repeatedly spun several times to get more accurate data. Once all data collected, the difference on both thermometers then is matched to the chart that has been worked out by meteorologist. The relative humidity of a certain area can be found easily in this way, the bigger the difference in temperature, the more humid the atmosphere.

How to use Sling Psychrometer

Digital Psychrometer - My Top Pick

Today, the development of technology has saved us from the trouble of doing the procedure in measuring humidity with sling psychrometer.

Digital psychrometer is a great instrument that provides practical use. With the same principle used in traditional psychrometer combined with smart computer, it can give accurate measure of relative humidity around.

Below is my top pick of Digital Psychrometer

Extech RH300 Humidity Meter with Dew PointMore Info

General Tools SAM990DW PsychrometerMore Info

General Tools EP8706 Digital PsychrometerMore Info

Extech RH390 Precision Dual Display Hygro Thermometer PsychrometerMore Info

Extech RH350 Psychrometer with 2 Type K Remote Temperature ProbesMore Info


Submit a Comment

No comments yet.