Temperature transmitter module 4-20mA wiring

Project Overview

　　Temperature transmitter module 4-20mA wiring

　　The temperature transmitter module is an indispensable part of industrial automation control systems, which can convert physical quantities such as temperature into standard 4-20mA current signals, making it convenient for PLC, DCS and other control systems to collect and process. Correctly understanding and mastering the 4-20mA wiring method of the temperature transmitter module is crucial for ensuring the stability and reliability of the system. This article will provide a detailed introduction to the 4-20mA wiring of temperature transmitter modules, helping you quickly master the wiring methods.

　　1、 The working principle of 4-20mA current signal

　　In the field of industrial automation, 4-20mA current signals are applied for signal transmission between sensors, transmitters, and actuators. The reason for choosing a 4-20mA current signal is because it has the following advantages:

　　Strong anti-interference ability: Current signals are not easily affected by electromagnetic interference and can be reliably transmitted in harsh industrial environments. Long transmission distance: Current signals can be transmitted over a long distance without significant attenuation. Easy to diagnose faults: When there is an open or short circuit in the signal line, the current signal will undergo significant changes, making it easier to detect and troubleshoot faults in a timely manner. The 4-20mA current signal is represented by a linear correspondence relationship to represent the measured value. For example, for a temperature transmitter with a measurement range of 0-100 ℃, when the temperature is 0 ℃, the output current is 4mA; When the temperature is 100 ℃, the output current is 20mA. By using a simple linear relationship, it is easy to convert current signals into corresponding temperature values.

　　2、 Common types of temperature transmitter modules

　　There are many types of temperature transmitter modules on the market, which can be divided into the following types according to the signal output method:

　　Two wire 4-20mA temperature transmitter: This type of transmitter uses two wires to simultaneously transmit power and signals, and has the advantages of simple wiring and low cost. It is suitable for applications that do not require high accuracy. Three wire 4-20mA temperature transmitter: This type of transmitter uses three wires to transmit the positive pole, negative pole, and signal of the power supply respectively. It has the advantages of high accuracy and strong anti-interference ability, and is suitable for occasions with high accuracy requirements. Four wire 4-20mA temperature transmitter: This type of transmitter not only provides 4-20mA current output, but also offers additional power input or signal output, making it more versatile and suitable for special occasions such as remote calibration and signal isolation. 3、 Temperature transmitter module 4-20mA wiring steps

　　The wiring method of the temperature transmitter module varies depending on the model. Taking common two-wire and three wire 4-20mA temperature transmitters as examples, the wiring steps are introduced below:

　　1. Wiring of two-wire 4-20mA temperature transmitter

　　The two-wire 4-20mA temperature transmitter only requires two wires to complete the wiring. The specific steps are as follows:

　　Connect the "+" end of the transmitter to the "+" end of the power supply. Connect the "-" end of the transmitter to the "+" end of the load. Connect the "-" end of the load to the "-" end of the power supply. It should be noted that the load resistance of a two-wire transmitter needs to match the output current of the transmitter, otherwise it will result in a decrease in measurement accuracy. The specific matching relationship can refer to the product manual of the transmitter.

　　2. Wiring of three wire 4-20mA temperature transmitter

　　The three wire 4-20mA temperature transmitter requires three wires to complete the wiring. The specific steps are as follows:

　　Connect the "+" end of the transmitter to the "+" end of the power supply. Connect the "-" end of the transmitter to the "-" end of the power supply. Connect the "S" end (or "I" end) of the transmitter to the "+" end of the load. Connect the "-" end of the load to the "-" end of the power supply. Unlike two-wire transmitters, the load resistance of three wire transmitters has a smaller impact on measurement accuracy, and an appropriate load resistance can be selected according to the actual situation.

　　4、 Wiring precautions

　　To ensure the normal operation of the temperature transmitter module, the following precautions should be taken when wiring:

　　Choose the appropriate power supply: The power supply voltage and current should meet the requirements of the transmitter, and pay attention to the polarity of the power supply. Ensure secure wiring: The wiring terminals should be crimped firmly to prevent poor contact from causing abnormal signal transmission. Pay attention to signal line shielding: To reduce signal interference, it is recommended to use shielded wires as signal transmission lines and reliably ground the shielding layer. Insulation treatment: In order to prevent short circuits, exposed wires need to be insulated after wiring is completed. 5、 Summary

　　The 4-20mA wiring of temperature transmitter modules is a fundamental task in industrial automation control systems. This article provides a detailed introduction to the working principle of 4-20mA current signals, common types of temperature transmitter modules, wiring steps, and precautions. It is hoped that this will help you better understand and master relevant knowledge. In the actual operation process, please carefully read the product manual and strictly follow the operating procedures to ensure the safe and stable operation of the system.