In the process of designing ventilation and air conditioning systems, experts carefully calculate the schemes and configurations of their installation. In addition to the structural device and location, external influences are also calculated. In particular, a quality installation cannot do without knowing in which direction and at what speed air flows will affect the object. For such calculations, an anemometer is also used - this is a device for measuring the characteristics of the wind, and in some modifications it also allows you to determine the temperature and humidity.
Device and principle of operation
All versions of this device are characterized by the presence of blades in the design, the movement of which gives information for taking into account the flow rate. That is, the principle of operation is based on the relationship between the wind speed itself and the heat transfer of tungsten elements, which are located on the air flow path and are heated by electric current. The characteristics of the air affect the heat flux generated by the power source of the device. Again, the anemometer is a device for measuring not only the wind, but also its temperature, so the sensors record several indicators at once. Also, various modifications are oriented to work in specific environments, including gas. Therefore, their use in the design of ventilation and air conditioning systems is undoubtedly the most common, but not the only purpose.
Main characteristics
As with any measuring instrument, the anemometer operator expects to receive accurate data. High-quality models from professional rulers are characterized by a modest error of about 5%. As for the measurement of temperature , the deviations can be 1-2 ° C. Compared to specialized thermometers, this is quite a lot, but for a multipurpose apparatus it is acceptable. Another important characteristic is the possible range of values that this device is able to fix in principle. Again, it should be borne in mind that the anemometer is both an apparatus for determining speed, and in some way a thermometer, therefore there will be at least two scales. The range of speed measurement usually ranges from 1 to 30 m / s. The temperature is often covered with negative values - for example, from -10 to 60 ° C.
Variants of the apparatus
There are two types of such devices - cup and vane. The first option is distinguished by the presence of a four-bowl cross in the design - their movement is a kind of information generator for obtaining wind speed data. This is a classic device that is used in private homes and in equipping production facilities. The vane anemometer is a compact device, the design of which consists of a vane device resembling a miniature fan. Again, the movement of the blades, activated by external air flows, is a signal for determining the characteristics of the wind. It is important to consider that the separation between these types of anemometers also takes place according to the method of use. Cup models are mounted perpendicular to the flows, and the wing models are located exactly in the direction of the wind.
Instrument Use Tips
Start working with the device after studying the controls. If the principle of operation can be general, then the designations in the display and the features of the provision of the final information can be individual in nature. Use the device only under conditions that are acceptable for a particular model. Many manufacturers, for example, caution against using the device in direct sunlight. The fact is that the anemometer is primarily a means of measurement, so any aggressive effect even on the body can affect its accuracy. The same applies to the increased dust content in air currents. After such use, thoroughly clean the blades or bowls of the anemometer.
The accuracy of the device may decrease not only due to a gross violation of the operating rules, but also over a long time. Therefore, to maintain the optimal level of reliability of the data provided, the anemometer is calibrated, which consists of several operations. At home, for example, it can be performed by analyzing the integrity of external surfaces, the correct installation of work items, and testing the function of the means of information output.
Anemometer Manufacturers
The segment of budget inexpensive models is represented mainly by domestic products. Such models can be found in the Megeon and Caliber ranges. Famous brands Geo-Fennel, ADA and Testo offer more solid modifications in functionality and reliability. These are high-quality devices from developers who specialize in the production of measuring equipment. In particular, the Testo anemometer already in entry-level models allows you to measure not only the speed and temperature of air flows, but also humidity. In addition, this company is developing modifications specifically designed for use in ventilation systems and ducts.
Price issue
The cheapest devices are available for 1.5-2 thousand rubles. These are typical classic devices that have a fairly high level of error and minimal functionality. Products from the same company Testo in the middle segment are estimated at 8-10 thousand. Such devices differ in accuracy of readings and the presence of additional protective shells, which allows them to be used in harsh conditions. If you need to measure the direction and speed of the wind with a minimum deviation from the actual indicators, then you should focus on the class of professional devices. These products are available at prices of about 20-30 thousand.
The nuances of choice
Relying on the choice is on the intended purpose. If the device is planned to be used privately to fix the main characteristics of the wind, then you can safely turn to the entry-level products. For more critical measurements, the additional functionality with which the anemometer is endowed should be taken into account. It can be a model with a digital display, automatic modes, backlight and modern display systems. Such equipment is usually used by professional builders, calculating the source data for installation operations.
Conclusion
Experienced users of measuring equipment do not recommend contacting devices that work with several characteristics. Practice shows that such devices are characterized by low accuracy and are often inconvenient to use. But in this case, a lot depends on which company produced the device. An anemometer from the premium Testo or ADA series, for example, may well replace even the functions of a hygrometer. Another thing is that the need for determining the indicators of humidity and temperature is not always associated with the need to monitor the characteristics of the wind. But in any case, do not neglect a comprehensive examination of external conditions. This will allow you to choose the right materials and structural schemes for installing those ventilation systems and duct shafts.