Everything You Need to Know About a Sling Psychrometer

A device called sling psychrometer is valuable for the measurement of the dry bulb as well as wet bulb temperatures at the same time. The fact that you are interested in this article means you know what those two temperatures are – but for the sake of everyone else’s knowledge, they are measurements of air humidity content.


The typical sling psychrometer australia has two primary and indispensable components, namely the dry bulb thermometer and the wet bulb thermometer. The former is a sensor bulb that contacts the air directly, where mercury is used as the sensing element. The latter is a sensor bulb covered with a wick of cotton or muslin covered in pure water. There’s a glass frame that serves as the protective housing of the instrument.



Moreover, there is a rotating handle usually attached to the housing. The design of the thermometer ensures that air in the web bulb will have immediate contact with the wet wick. As soon as the thermometer bulb exposes itself to a combination of air and water vapour, the temperature shown by the instrument is the dry bulb temperature.


Meanwhile, if the bulb of the thermometer has a wet wick covering in it and when the bulb covered by the wet wick gets exposed to water and air vapour, the temperature reading reflects that of the temperature of the web bulb.


The different applications for a sling psychrometer australia include:


  • Checking the humidity level in rooms with air conditioning systems.
  • Setting and checking hair hygrometer
  • Measuring the range of 0 to 100% RH
  • Measuring wet bulb temperature from 0’C to 180’C.


It is worthy of mention that an accurate measurement of the wet bulb temperature can only be achieved once the air moves with speed around the wet wick. The psychrometer must spin to obtain the air velocity.


One of the thermometers in the device that’s covered with the wet wick will contact with the air, and when it goes through the wet wick in the thermometer bulb, the moisture found in the wick will start evaporating, thereby creating a cooling effect in the bulb. It is given that the temperature indicated by the thermometer with the wet bulb thermometer is lower than that of the temperature of the dry bulb.


While a sling psychrometer appears to be the definition of a complete and versatile instrument, there is no denying that it also has its limitations. For instance, you cannot use the instruments in scenarios where there are automation requirements. You also cannot use the device if you’re looking at continuous recording. Meanwhile, you must see to it that the wick isn’t covered with dirt because it will compromise its water absorption capability.