Stability of signal transmission
The impact of good quality: high-quality wiring terminals can ensure the accuracy and stability of signal transmission. The metal conductor inside is made of excellent material, such as high-purity copper, which has good conductivity and can effectively reduce the attenuation of signals during transmission. In the PLC control cabinet, the transmission of analog signals (such as 4-20mA current signals or 0-10V voltage signals) is very critical. High-quality wiring terminals can ensure that these weak signals are accurately transmitted from the sensor to the analog input module of the PLC, so that the signal received by the PLC truly reflects the status of the field equipment, thereby ensuring the accuracy of the control system.
The impact of poor quality: poor-quality wiring terminals may have poor metal conductor material, such as copper alloys containing more impurities, which have a larger resistance. During the signal transmission process, it will cause serious signal attenuation. For digital signals, signal distortion may occur, making it impossible for the PLC to correctly identify whether the signal is “0” or “1”, thereby causing malfunction of the control system. For example, in an automated packaging production line, the product arrival signal sent by the sensor may be distorted due to the poor quality of the terminal block, causing the PLC to fail to correctly trigger the action of the packaging machine, resulting in confusion in the packaging process.
Electrical safety performance
The impact of good quality: Good quality terminal blocks perform well in electrical insulation performance. The shell material is generally made of high-quality engineering plastics with high insulation strength and good flame retardancy. This can effectively prevent short circuits between different terminal blocks and protect the safety of electrical equipment in the PLC control cabinet. At the same time, in some special environments (such as humid environments), high-quality terminal blocks can prevent leakage and ensure the safety of operators. For example, in the PLC control cabinet of a sewage treatment plant, the surrounding humidity is high, and good quality terminal blocks can avoid electrical accidents caused by moisture.
The impact of poor quality: The insulation material of poor quality terminal blocks may not be of good quality and is prone to aging and cracking. This will lead to a decrease in insulation performance, and short circuits may occur between wires of different polarities. Once a short circuit occurs, the input and output modules of the PLC may be damaged, and even an electrical fire in the control cabinet may occur. Moreover, if the poor insulation performance leads to leakage, the control cabinet housing will be charged, posing a serious threat to the life safety of the operator.
Mechanical performance and service life
The impact of good quality: The mechanical structure of high-quality terminal blocks is reasonably designed and has good clamping force. When the wires are connected, they can firmly clamp the wires to prevent them from loosening. During the operation of the control cabinet, the wires can still maintain a good connection state when affected by factors such as vibration and temperature changes. It has a long service life and can maintain stable performance during long-term use, reduce equipment downtime caused by terminal failure, and improve the reliability and economy of the entire PLC control system.
The impact of poor quality: The mechanical clamping force of poor-quality terminal blocks is insufficient. During the operation of the control cabinet, especially when subjected to vibration, the wires are easy to loosen. Loose wires can cause poor contact and generate arcs. The arc will further damage the terminal blocks and wires, and may interfere with the surrounding electrical signals. Moreover, poor-quality terminal blocks have a short service life and may be damaged in a short time, requiring frequent replacement, increasing maintenance costs and the risk of equipment downtime.
