Radiated electromagnetic interference (EMI) originates from various sources such as power networks, electrical equipment transients, lightning, radio, TV, radar, and high-frequency induction heating systems. This type of interference is often complex in distribution and can significantly affect the performance of a PLC system if it is located within an RF field. The interference typically occurs through two main pathways: direct radiation onto the PLC or its circuits, inducing unwanted signals, and radiation into the communication network, causing disturbances on the communication lines. External leads can also introduce interference into the system. For example, the power supply of the PLC system, which is usually connected to the grid, can be affected by electromagnetic noise from the grid itself. Changes in the power grid, switching operations, large-scale equipment start/stop, and harmonics from AC/DC transmission can all result in voltage fluctuations and disturbances that are transmitted through the power lines. Although isolated power supplies are commonly used, they may not provide perfect isolation due to factors like distributed capacitance and manufacturing limitations. Signal lines are another common source of interference. These lines, which carry information between devices, can also pick up external noise. This can happen either through the power supply of the transmitter or via electromagnetic radiation from the surrounding environment. Such interference can lead to abnormal operation of output signals, reduced measurement accuracy, and even damage to components in severe cases. In poorly isolated systems, signal crosstalk can cause data corruption, logical errors, and system crashes. Grounding is a crucial method for improving electromagnetic compatibility. Proper grounding helps suppress EMI and prevents incorrect grounding, which can otherwise create serious interference. However, improper grounding can lead to malfunctions and instability in the system. Internal components of the PLC system can also generate interference through mutual electromagnetic radiation. For instance, logic circuits can interfere with analog circuits, and mismatched ground connections (such as analog vs. logic grounds) can cause issues. These problems fall under the electromagnetic compatibility design of the PLC manufacturer and are generally not modifiable by end users. Therefore, selecting modules with proven performance or undergoing thorough testing is essential for ensuring reliable operation.
Electric Motor For Wire-drawing Machine
Electric Motor For Wire-Drawing Machine,Multi-Type Electric Motor,Adjustable Speed Motor,Multiple Satisfaction Motor
Jiangsu Hengchi Motor Technology Co., Ltd , https://www.hcemotor.com