How to choose a temperature and humidity meter and a brief introduction 1. How to choose a thermometer and hygrometer Because of different temperature and humidity measurement principles, there are various temperature and humidity instruments. When selecting, consider the actual application environment and requirements of the user, such as range, output, and display. , installation methods, sampling methods, gas types, materials and structures, control monitoring requirements, environmental hazards, etc. In addition, factors such as cost-effectiveness and maintenance workload should also be considered:
a. Rugged: The hygrometer's sensors and housing must be considered for condensation, drying, extreme temperatures, dust, chemicals, or other contamination.
b. Cost-effectiveness: When using temperature and humidity instruments, it is not enough to consider only low prices. It should be selected based on comprehensive price and performance. This includes price, life, maintenance, and calibration costs. Verification: The method of verification and whether it is easy to consider, even if you do not need high-precision results. It will save you the workload of checking a convenient instrument on site and in situ.
c. Adaptability: When the use situation is not a single one, consider the adaptability of the instrument. Replaceability: It is generally desirable that the hygrometer can be used interchangeably or with other probes to match your host. Maintenance: Check the time required for regular cleaning, renewal, and replacement of hygrometers.
d. Quality Reliability, Average Lifetime: When the quality is not good, you can start from the overall impression, examine the quality appraisal and factory standards, and examine the history, reputation, market share and application of the manufacturer. The brand-name products are better than the general products. Manufacturers' products are better than manufacturers, and consulting other users is also a good method.
II. Working principle of hygrometer The hygrometer is used to measure the temperature and humidity of the environment. In order to facilitate the measurement, the measuring temperature meter and the measuring humidity meter are used together to determine the environmental conditions of production or storage. It also applies to people's daily life. The application is more extensive.
Absolute humidity: The pressure p of water vapor in the air is called the absolute humidity of the air.
The humidity of the air can be expressed by the density of the water vapor contained in the air, that is, the mass of water vapor contained in the unit volume of air. Because it is difficult to directly measure the density of water vapor in the air, and the pressure of water vapor increases with the increase of water vapor density, the air humidity is usually expressed by the pressure of water vapor in the air. This is the absolute humidity of air.
The hygrometer measures the principle of relative humidity and temperature: The temperature of the wet bulb thermometer is always lower than that of the dry bulb thermometer. Temperature readings (temperature), the temperature difference, are related to how quickly the water evaporates (ie relative humidity at the time). Based on the reading of the two thermometers, the relative humidity of the air can be detected from the table or curve.
XP SERIES MAGNETIC CONTROLLING PIPRLINE CRAWLER is new generation pipeline welds testing equipment. by adopts magnetic remote control technology, this series Pipeline Crawler uses a magnetic control box instead of traditional gamma source control so that it can avoid radiation harm to the people, which is more suitable for off land engineering.
Pipeline Crawler
Pipeline Crawler,Pipe Inspection Camera ,Pipe Crawler,Pipeline Crawler X Ray Machine
Dandong Nondestructive Testing Equipment Co., Ltd. , http://www.ddchinaxray.com