温度变送器是一种将温度变量转换为可传送的标准化输出信号的仪表。把温度传感器的信号转变为电流信号，然后再连接到二次仪表上，从而可以显示出对应的温度。目前，技术已经非常成熟了，在各工厂中非常常见，主要可以应用于石油、化工、化纤；纺织、橡胶、建材；电力、冶金、医药；食品等工业领域现场测温过程控制；特别适用于计算机测控系统,也可与仪表配套使用。

       A temperature transmitter is a meter that converts a temperature variable into a standardized output signal that can be transmitted.The signal of the temperature sensor is converted into a current signal,which is then connected to the secondary meter so that the corresponding temperature can be displayed.At present,the technology is very mature,very common in various factories,mainly used in petroleum,chemical,chemical fiber;textile,rubber,building materials;electric power,metallurgy,medicine;food and other industrial fields on-site temperature measurement process control;especially suitable for The computer measurement and control system can also be used with the instrument.

       温度变送器需要定期进行校验吗？

       Does the temperature transmitter need to be verified periodically?

       预热器测温采用的测温元件有热电阻和热电偶，热电阻测温的范围比较小，而预热器的温度达1000多摄氏度，因此，采用热电偶测温是.有效的手段。热电偶分为一体化热电偶和非一体化热电偶。在我们公司多采用非一体化的热电偶，通过温度变送器将电信号转变成为温度信号传递给中央控制室，供操作员参考。非一体化热电偶采用两线制，通过温度变送器连接公司的DCS系统，返回中控室，在测量过程中，有的变送器受环境的影响较大，零点和满点会发生不同程度的漂移，这就需要有效的手段对其进行及时准确的校准。

        The temperature measuring components used in the preheater temperature measurement have thermal resistance and thermocouple.The range of thermal resistance temperature measurement is relatively small,and the temperature of the preheater is more than 1000 degrees Celsius.Therefore,temperature measurement by thermocouple is the most effective means.Thermocouples are divided into integrated thermocouples and non-integrated thermocouples.In our company,we use non-integrated thermocouples to convert electrical signals into temperature signals through temperature transmitters for transmission to the central control room for operator reference.The non-integrated thermocouple adopts two-wire system,and is connected to the company's DCS system through a temperature transmitter,and returns to the central control room.During the measurement process,some transmitters are greatly affected by the environment,and zero and full points will occur to different degrees.The drift,which requires effective means to timely and accurately calibrate it.

       校验方法：

       Calibration method:

       1、校验时，在输入端接入电位差计，输出信号为电动势，在输出端接上24VDC稳压电源并串接上标准电流表。

       1.During calibration,connect the potentiometer to the input terminal,the output signal is the electromotive force,connect the 24VDC regulated power supply to the output terminal and connect the standard ammeter in series.

       2、调零：反接信号输入线，使电位差计输出校验现场室温对应电动势，调整电位器Z，使电流表读数为4mA。

       2,zero adjustment:reverse signal input line,so that the potentiometer output verification site temperature corresponding to the electromotive force,adjust the potentiometer Z,so that the ammeter reading is 4mA.

       3、调满：正接信号输入线，使电位差计输出满量程对应电动势，调整电位器S，使电流表读数为20mA。（该电动势为满度电动势减去室温对应电动势后的值）

       3,full:the signal input line is connected,so that the potential difference meter outputs the full range corresponding to the electromotive force,adjust the potentiometer S,so that the ammeter reading is 20mA.(The electromotive force is the value of the full-scale electromotive force minus the room temperature corresponding to the electromotive force).

       注意事项：

       Precautions:

       1、接线时要注意极性，并且在通电预热15分钟后开始调校。

       1.Pay attention to the polarity when wiring,and start tuning after 15 minutes of power-on preheating.

       2、调校中以缓慢的速度输入信号，以保证不产生过冲现象。

       2.In the adjustment,input the signal at a slow speed to ensure that there is no overshoot.

       3、在调整时不要用力过猛，防止拧坏。

       3.Do not use excessive force during adjustment to prevent screwing.

       4、调校前，要准备好校验记录单，并查热电偶在各校验点的温度/毫伏对照表或热电阻温度/电阻对照表，将调校温度变送器需要的数据查出并填入已经准备好的数据记录表中。

       4.Before calibration,prepare the calibration record sheet,and check the temperature/millivoltal comparison table or the thermal resistance temperature/resistance comparison table of the thermocouple at each checkpoint,and adjust the data required by the temperature transmitter.Exit and fill in the prepared data record table.