Talking about the Main Work of Preventing Lightning Strike by Electronic Truck Scales

How does the electronic truck scale prevent lightning? Thunder and lightning will cause strong changes in the atmospheric electromagnetic field, the main manifestations of three kinds of physical processes: First, electrostatic induction, that is ground lightning caused by lightning changes in the atmosphere, so that the conductor near the flash receiving object induced charge, the formation of a high potential difference to the ground Second, electromagnetic induction, that is, the current in the lightning channel changes with time, forms a changing electromagnetic field in the space around it, and generates an induced voltage and an eddy current on the conductive object attached to the channel. Third, electromagnetic radiation is generated by the lightning channel. The rapid change in current is formed. Since the electronic truck scale is only resistant to low pressure, the above three physical processes caused by lightning are extremely destructive, especially electromagnetic induction. The more advanced the microelectronic device, the smaller the power consumption, and the more sensitive, the more destructive. Therefore, the electronic truck scale to prevent lightning strikes should do the following work:

1. Lightning rods should be placed over the scale body to neutralize the charges in the clouds in the tip discharge effect so that the electronic truck scales will not be damaged by lightning. The height of the lightning rod can be determined according to the length of the electronic truck scale, and the lightning rod protects a circular area whose radius is equal to its height.

Second, the entire scale platform should be grounded. Connect the scale body to the grounding pile with one or several grounding cables. The grounding pile should be grounded in a zero zone where the potential is constant, and the grounding resistance is less than 4. There is a large high-current backflow channel between the weighing platform and the grounding pile, so when the static electricity is induced, the electrons can be supplemented from the earth to make it neutralize. After the equipment generates a high potential, it can quickly evacuation without damaging the electronic truck scale.

Third, each sensor must have protective grounding. Therefore, a grounding wire should be set for each sensor position, and a grounding pile should be set between the sensor and the ground. The grounding wire should be reliably connected to the grounding pile or the grounding wire must be connected to the nearest anchor bolt. However, the anchor bolts must be connected to the reinforcing steel grounding net in the foundation.

Fourth, the metal threaded pipe that passes the signal cable must also be connected to the grounding grid.

5. The shield of the load cell signal cable must be grounded. When the electronic truck scale is powered by the mains power grid, there is a long distance from the power distribution room to the installation site. The weighing platform and the scale room also have a signal cable with a distance of less than the distance. It is not difficult to imagine that lightning strikes through the electromagnetic induction route in the lead. The introduction of high potential, it may cause damage to the weighing instrument, therefore, the signal line of the load cell and the current power line that excites the load cell are connected by a cable that grounds the shield to eliminate electromagnetic induction lightning damage or cause Explosion may be possible. The shield layer of the load cell signal cable can be connected to the grounding wire of the load cell, or it can be connected to the grounding stake of the weighing display; it can be determined according to the site conditions, but it is not allowed to have two points respectively with the two grounding piles.

Six, weighing display instrument shell to ground. therefore. A grounding pile is set in the grounding scale room, and is connected with the reinforcement mesh (grounding) in the foundation of the scale. When a plastic shell is used, a metal film should be sprayed on the inner surface of the shell and then grounded.

VII, the junction box should be grounded. Junction box to set the grounding line and scale body connected.

VIII. The power supply must be grounded and it must be equipped with a surge protection device.

Doing the above points will greatly enhance the safety and reliability of electronic scales, especially those users in Dorayan area must pay attention to the above requirements when installing electronic truck scales to ensure the safe use of electronic truck scales.