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首先，必须选择传感器的结构，使敏感元件的规定的测量时间之内达到所测流体或被测表面的温度。 Firstly, the structure of the sensor must be selected to measure the temperature of the measured fluid or the surface under the measured time of the sensitive component. 在大多数情况下，对温度传感器的选用，需考虑以下几个方面的问题： In most cases, the selection of temperature sensors should consider the following aspects: (1) 被测对象的温度是否需记录、报警和自动控制，是否需要远距离测量和传送。 (1) whether the temperature of the measured object needs to be recorded, alarm and automatic control, whether it needs to be measured and transmitted over a long distance. (2) 测温范围的大小和精度要求。 (2) the size and precision of the temperature measuring range. (3) 测温元件大小是否适当。 (3) whether the temperature measuring element is suitable. (4) 在被测对象温度随时间变化的场合，测温元件的滞后能否适应测温要求。 (4) if the temperature of the measured object varies with time, the delay of the temperature measuring element can be adjusted to the temperature measurement requirement. (5) 被测对象的环境条件对测温元件是否有损害。 (5) the environmental conditions of the tested objects are harmful to the temperature measurement elements. 湿度传感器的选择主要是根据测量范围。当测量范围预计在总量程之内，可选用铂电阻传感器。较窄的量程通常要求传感器必须具有相当高的基本电阻，以便获得足够大的电阻变化。热敏电阻所提供的足够大的电阻变化使得这些敏感元件非常适用于窄的测量范围。如果测量范围相当大时，热电偶更适用。最好将冰点也包括在此范围内，因为热电偶的分度表是以此温度为基准的。已知范围内的传感器线性也可作为选择传感器的附加条件。 The selection of humidity sensor is mainly based on the measurement range. Platinum resistance sensor can be used when measurement range is expected within the total range. A narrower range usually requires that the sensor have a fairly high base resistance to gain enough resistance variation. The resistances provided by thermistors are large enough to make these sensitive elements very suitable for narrow measurement ranges. The thermocouple is more applicable if the measurement range is fairly large. It is best to include the freezing point in this range because the thermocouple's scale is based on this temperature. The sensor linearity of the known range can also be used as an additional condition for selecting the sensor. 响应时间通常用时间常数表示，它是选择传感器的另一个基本依据。当要监视贮槽中温度时，时间常数不那么重要。然而当使用过程中必须测量振动管中的温度时，时间常数就成为选择传感器的决定因素。 Response time is usually represented by the time constant, which is another basic basis for selecting a sensor. Time constants are less important when monitoring the temperature in the tank. However, when the temperature in the vibrating tube must be measured in the process, the time constant becomes the determining factor in selecting the sensor. 动态温度的测量比较复杂，只有通过反复测试，尽量接近地模拟出传感器使用中经常发生的条件，才能获得传感器动态性能的合理近似 The measurement of dynamic temperature is more complicated. Only by repeated testing, it can simulate the conditions of the sensor in the use of the sensor, so as to obtain the reasonable approximation of the dynamic performance of the sensor