无源无线测温系统是一款测温系统， 具有多种温度监测方式。目前应用最广泛的有三种。第一种是CT式，通过CT取电为传感器供电，但由于线路电流不一定，所以供电也不稳定，而传感器本身消耗能量的方式有限，长期大电流工作可能导致自身发热从而影响测温准确性。第二种是表面声波式，通过声波在不同温度环境下传播速度不同从而测量温度，此种方法同红外测温类似。第三种为RFID技术，主机通过一个发射机发射能量给无源传感器，传感器接收能量以后实现温度测量，然后通过无线回传给主机。
Passive wireless temperature measurement system is a temperature measurement system, with a variety of temperature monitoring methods. At present, there are three widely used ones. The first one is CT type. The sensor is powered by CT, but the power supply is not stable because the line current is not certain, and the energy consumption of the sensor is limited. Long-term high current operation may lead to its own heating and affect the accuracy of temperature measurement. The second is the surface acoustic wave type, which measures the temperature by the sound wave propagating at different speeds in different temperature environments. This method is similar to infrared temperature measurement. The third kind is RFID technology. The host transmits energy to the passive sensor through a transmitter. The sensor receives the energy to realize the temperature measurement, and then transmits it to the host wireless.
主要优点：1、无需电池或电源 2、不易老化无污染 3、与开关柜同寿命
Main advantages: 1, no battery or power supply 2, no aging, no pollution 3, same life as switchgear.
4、适应不同的环境 5、精度高无电位差 6、不受电磁波干扰
4, adapt to different environments 5, high accuracy, no potential difference 6, no electromagnetic interference.