There are usually two goals for improving the grounding of the grounding system in coal preparation equipment: one is for safety, and the other is to suppress harassment. The improved grounding system is one of the important countermeasures for the PLC control system of coal preparation equipment to resist electromagnetic disturbance. The system grounding method usually has three methods: floating ground method, direct ground method and capacitive grounding. For the PLC control system, it is a high-speed and low-level control device. It should be used for direct connection. Due to the influence of information cable dispersion capacitance and input device filtering, the information exchange frequency between devices is usually lower than 1MF, so choose One-point grounding and one-point grounding methods in series are selected for the grounding wire of the PLC control system of coal equipment. The collectively deployed PLC system is suitable for one-point grounding method in parallel, and the center connection of the cabinet of each device is led to the grounding electrode by its own grounding wire. If the distance between the devices is large, the one-point grounding method in series should be used, and a large cross-section copper bus bar is used to connect the center of the cabinet of each device, and then the ground bus bar is directly connected to the ground electrode!

When the information source is grounded, the shielding layer should be grounded on the information side; when it is not grounded, it should be grounded on the PLC side. The functions of grounding are:

One is to eliminate the noise voltage that occurs when each circuit current passes through a common ground impedance;

Second, there is a potential difference between the controller and the control panel and the ground. Good grounding can reduce the disturbance current caused by the potential difference;

The third is the harassment mixed into the power supply and input information, which can be introduced into the earth through a good grounding, thereby reducing the impact of the harassment: good grounding can also prevent the sensory voltage caused by the current.

This article focuses on the countermeasures against grounding chaos disturbance of coal preparation equipment. If you want to know more details about coal preparation equipment, please directly relate to us. We will answer you religiously!