Temperature and humidity transmitter in the purchase, there are many technical parameters to be determined, how can we choose a temperature and humidity transmitter suitable for their own on-site working conditions? Today, we will take you to understand it together by our Xingyi Wang Technology. First, select the measurement range As with pressure transmitters and temperature transmitters, when selecting a temperature and humidity transmitter, the measurement range must first be determined. In addition to meteorological and scientific research departments, temperature and humidity measurement and control generally do not require full humidity range (0-100%RH) measurement. The humidity range is usually 5%~95%RH. The temperature range is between -40~85 °C. Second, select the measurement accuracy Measurement accuracy is an important indicator of temperature and humidity transmitters, and every percentage point increase is a step up or even a grade for temperature and humidity transmitters. Because to achieve different precision, the manufacturing cost varies greatly, and the selling price is also very different. Therefore, users must be tailor-made, and should not blindly pursue “high, precise and sharp”. Temperature severely affects the relative humidity in a given space. 0.1°C per change in temperature. A humidity change (error) of 0.5%RH will result. If it is difficult to achieve constant temperature in the use occasion, it is inappropriate to propose too high humidity measurement accuracy. In most cases, if there is no precise means of temperature control, or if the measured space is non-sealed, an accuracy of 5%RH ± is sufficient. For local spaces that require precise control of constant temperature and humidity, or occasions where humidity changes need to be tracked and recorded at any time, then choose a temperature and humidity transmitter with an accuracy of more than ±3%RH. The requirements for accuracy higher than ±2%RH may be difficult to achieve even the standard humidity generator for calibrating the transmitter, let alone the temperature and humidity transmitter itself. Relative humidity measuring instruments, even at 20-25 °C, it is still difficult to achieve an accuracy of 2%RH. Third, consider time drift and temperature drift Temperature and humidity transmitter in actual use, due to the influence of dust, oil and harmful gases, the use time is long, the electronic humidity transmitter will produce aging, accuracy decreases, the annual drift of the electronic humidity sensor is generally about ±2%, or even higher. Under normal circumstances, the manufacturer will indicate that the effective use time of 1 calibration is 1 or 2 years, and it needs to be recalibrated after expiration. Fourth, other selection considerations Temperature and humidity transmitters are non-sealed, in order to protect the accuracy and stability of measurement, should be avoided in acidic, alkaline and organic solvent-containing atmospheres. It is also avoided in dusty environments. In order to correctly reflect the humidity of the measured space, it should also be avoided to place the temperature and humidity transmitter too close to the wall or in a dead corner where the air does not circulate. If the room under test is too large, multiple humidity and temperature transmitters should be placed. Some temperature and humidity transmitters have high requirements for power supply, otherwise it will affect the measurement accuracy. Or the temperature and humidity transmitters interfere with each other, or even fail to work. When using, it should provide a suitable power supply that meets the accuracy requirements according to the technical requirements. If the temperature and humidity transmitter needs to transmit signals over long distances, pay attention to the attenuation of the signal. When the transmission distance exceeds 200m, it is recommended to choose a temperature and humidity transmitter with current output signal. Product consultation, product customization, agent, technical inquiry, quotation, etc. If you have any questions, please contact Xingyi: 400-600-4496!