Specification for the use of temperature and humidity sensors

Guangzhou Zhongxin has accumulated years of experience and technology to summarize the correct usage standards of temperature and humidity sensors as follows:

1. From the measurement range

The first step in selecting a humidity sensor is to determine the measurement range. Except for meteorological and scientific research departments, temperature and humidity measurement and control generally do not require full humidity range (0-100% RH) measurement.

2. Accurate measurement accuracy

Measurement accuracy is the most important indicator of humidity sensors, and every improvement is significant; Flash; One percentage point, for humidity sensors, is a step up, or even a level up. Because to achieve different accuracies, the manufacturing costs and selling prices vary greatly. So users must tailor their products to suit their needs and should not blindly pursue them; Ldquo; High, refined, and sharp& Rdquo;. If humidity sensors are used at different temperatures, the indication value should also consider the impact of temperature drift. As is well known, relative humidity is a function of temperature, which seriously affects the relative humidity in a designated space. Every 0.1 ℃ change in temperature. A humidity change of 0.5% RH will be generated (error). If it is difficult to achieve constant temperature in the usage situation, it is not appropriate to propose excessively high humidity measurement accuracy. In most cases, if there is no precise temperature control method, or if the measured space is unsealed; Plusmn; A precision of 5% RH is sufficient. For local spaces that require precise control of constant temperature and humidity, or for situations where humidity changes need to be tracked and recorded at any time,& Plusmn; Humidity sensor with an accuracy of 3% RH or higher. And the accuracy is higher than& Plusmn; The requirement of 2% RH may not even be achievable with a standard humidity generator for calibrating sensors, let alone the sensors themselves. Relative humidity measuring instrument, even at 20& Flash; It is still difficult to achieve an accuracy of 2% RH at 25 ℃. The characteristics given in the product documentation are usually measured at room temperature (20 ℃± 10 ℃) and in clean gas.

3. Consider the issues of time drift and temperature drift

In practical use, due to the influence of dust, oil stains, and harmful gases, electronic humidity sensors will age and decrease accuracy over a long period of use. The annual drift of electronic humidity sensors is generally within& Plusmn; About 2%, or even higher. In general, the manufacturer will indicate that the effective use time for one calibration is 1 or 2 years, and a new calibration is required upon expiration.

4. Other precautions

Humidity sensors are non sealed, and to protect the accuracy and stability of measurements, they should be avoided as much as possible in acidic, alkaline, and organic solvent containing atmospheres. Also avoid using in dusty environments. To accurately reflect the humidity of the space to be measured, it is also necessary to avoid placing the sensor in a dead corner that is too close to the wall or has no air circulation. If the room being tested is too large, multiple sensors should be placed. Some humidity sensors have high requirements for power supply, otherwise it will affect measurement accuracy. Or sensors may interfere with each other and even fail to function. Suitable and accurate power supply should be provided according to technical requirements during use. When sensors need to transmit signals over long distances, attention should be paid to the issue of signal attenuation. When the transmission distance exceeds 200m or more, it is recommended to choose a humidity sensor with frequency output signal.

Guangzhou Zhongxin Main Brand:

Load Cell:Mettler Toledo weighing sensor from Switzerland, HBM weighing sensor from Germany, Transcell weighing sensor from the United StatesHeavy sensor, Celtron weighing sensor from the United States, Tedea huntleigh weighing sensor from the United States, Vishay Revere from the United StatesLoad cells, Sensortronics load cells from the United States, FLINTEC load cells from Germany, RICE LAKE from the United StatesLoad cells, BLH load cells in the United States, NOBEL ZEMIC load cells in the United States, and Mkcells weighing in the United StatesSensors, Coriolis load cells, Suncells load cells from the United States, Chcontech load cells from the United States, United KingdomOAP weighing sensor, Guangshi weighing sensor, Italian Laumas weighing sensor, Italian N.B.C. sensor, ItalianDali AEP weighing sensor, Spain Utilcell weighing sensor and display, Japan NMB weighing sensor, JapanNTS weighing sensor, Korean Bongshin weighing sensor, Korean DACELL weighing sensor, Korean Fine weighing sensorSensors, Korean CAS weighing sensors, German Sartorius weighing sensors, German Soemer weighing sensors;

Displacement sensor:German Novotechnik displacement sensor, German VOLFA displacement sensor, German HBM displacement sensorTrans-Tek displacement sensor from the United States, MEAS displacement sensor from the United States, RDP displacement sensor from the United Kingdom, MTS displacement sensor from the United StatesSensors;

Pressure sensor:MSI pressure sensor in the United States, MEAS in the United StatesPressure sensorJapanese NMB pressure sensor, German BDSensor pressure sensor, German HBM pressure sensor, German Burster pressure sensor, American FUTEK pressure sensorSensors, Dytran pressure sensors from the United States, SENSYS pressure sensors from South Korea;

Temperature and humidity sensors:Austrian E+E temperature and humidity sensor;