Why do you need shielded cables in many transmitter sites? This has to do with the characteristics of the shielded cable. We all know that in the process of using the instrument, if there is signal interference, it is bad. The use of shielded cables in instrumentation will greatly reduce the occurrence of this situation. The shielding layer of the cable screen is generally a mesh woven with metal wires to prevent the electromagnetic interference signal from being superimposed on the normal signal, causing measurement and control errors, and even affecting the normal operation of the control system and secondary instrument. How to connect the instrument and the shielded cable to effectively reduce the electromagnetic interference signal and superimpose it on the normal signal? This requires that the shielded cable must be grounded. Specifically, there are several methods. First, the control room side is grounded, and the field end is floating. In most cases, the instrument cable shield is floating at the field end, grounded on the side of the control room, and generally connected to the working grounding bus bar of the control cabinet and dashboard. Second, the side of the control room floats in the air, and the site end is grounded. The instrument cable shield is also grounded at the end of the field and floats on the side of the control room, such as grounding thermocouples, pH meter solutions, electromagnetic flowmeters, etc., which should be grounded in accordance with the requirements of the information provided by the instrument manufacturer in the application. Third, in practical applications, there are also some requirements that the signal loop, signal source, and the common end of the receiving instrument should be grounded, in this case, an electrical isolator should be used to isolate the two grounding points. Fourth, the electrical continuity of the cable shield. In practical application, the field junction box is usually used to connect each instrument signal cable (sub-cable) to the field junction box, and then a multi-core shielded cable (main cable) is connected to the control cabinet and instrument panel installed in the control room. If you have any questions about product consultation, product customization, agency, technical inquiry, quotation, etc., please contact Xingyi, 400-600-4496!