Lightning can be harmful to coil based equipment if the equipment is not connected to the supply or switched off from supply line?
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| Natural Lightning Effects on Coil based equipment [figure 1] |
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| Natural Lightning Effects on Coil based equipment [figure 2] |
Introduction
Natural Lightning have many theories .Before discussing this topic, let us first say that this subject has been discussed by many theories, which are significant for discussing this subject and The theory that will help readers understand this is discussed here. This theories defined many way but the basis structure of theory always same.
What is Natural Lightning?
When water evaporates from the earth's surface and rises to form clouds. Rain and thunderstorms occur when that cloud loses its water holding capacity.Now the question is why lightning.
The particles of water that rise from the surface of the earth,In it small water particles have negative charge and large water particles have positive charge.
These small water droplets rise to form negatively charged clouds and large water droplets form positively charged clouds.
We know that positive charge particles and negative charge particles always attract each other and try to neutralize itself.
So a positively charged cloud and a negatively charged cloud are attracted to each other and they try to neutralize each other, resulting in a huge amount of electricity,heat, light and noise this is called Natural Lightning. The amount of Lightning depends upon the amount of charge interact each other. We know electric current always flow low reactance path. When charge particle interact each other . A huge neutralize strike are developed.
This lightning strike finds a low reactance path or try to ground. When lightning occurs, lightning tries to find a low reactance path, as the amount of plantation on the surface is high. So for him, lightning is seen to be taught more in plants and so lightning tries to hit in that direction.
lightning strikes
We know that the Earth's surface is a huge reservoir of positive charges so negatively charged clouds are sometimes attracted by the Earth's surface.When lightning strikes the earth's surface, it generates a lot of electricity.This is how lightning is created on the earth's surface. Let us now answer our question.
If the power supply of any electrical equipment is off or the power supply is closed circuit but if the equipment is internally short circuit then there is a highly chance that it will be damaged by lightning.
When lightning strikes the surface, a large amount of electrical energy is generated and mutually linked with nearby coil based electrical instrument according to the destiny of the mutual inductance. Always mind lightning strike always find low reactance. If it can be find nutralize electricity is huge . If it mutualy inducted to any coil the coil will brun .
Example: Trees are the most low reactive objects on Earth. Lightning strikes when falling into a tree. Then the neutralized electricity and any coil equipment can be destroyed.
In other words, the electric current generated by the lightning creates the mutual inductance of the close circuit coil near it and for this mutual inductance current flows through the coil since the amount of lightning voltage not limited so induced current in coil is not limited.
The most important thing about burning the coil here is that the coil is internally short circuited. Also another issue is whether the coil may burn out if the electrical instrument is not supplied but connected to the electrical circuit.
However, the huge lighting voltage can enter the instrument through the operating switch of the instrument. Since the distance between the two contacts of the switch is very limited, the huge lighting voltage can easily reach from one contact to another through the arc and burn the coil.
Some devices designed to solve this type of problem The device used to solve this type of problem is the lighting arrester.The function of a lighting arrester is to store the positive charge on the surface.
When lightning strikes, the lightning will attract the lighting arrester and the heavy lighting voltage will be grounded through the lighting arrester.
The lighting arrester will attract and ground the lightning before the huge lighting voltage is available to induce in any coil based electrical instrument.
Lightning protection equipments
The trident shape in the house usually uses a surge arrester. It is usually made as an alloy of cadmium copper. Cadmium provides firmness and copper creates low reactance pathways. Usually a surge arrester creates a cloud of negative electrons. And through which the lightning surge is attractive and due to the low reactance path the lightning arrester becomes grounded through it.
Also in case of transmission line low voltage or high voltage a ground war catenary is used to intercept the lighting surge. This type of system is usually the most active in traction systems. Where surge can pose a big danger.
Also the poles or structures of the transmission line are from such a high direction. And the lighting charge is more attractive for the flow of negative electrons in the layer.
Even if there is a catenair net at the electrical substation, it is not enough for lightning surge. For this a special device is used which is called Sarge Arrester. It is usually used to protect any equipment.
Lightning Arrester Installation
Usually lightning Arrester use a specific earthing system . Depending of the system capacity the type of earthing system use . Some time rod earthing can be use or some time pipe and sheet earthing use. The lighting Arrester Install in Rooftop .
Lightning Arrester connected to ground equipment by galvanized wire for reduce the cost of installation . But due long life and properly made low reactance Copper wire must be used. In this system, earthing is most important. Here If some compromise or negligence for installation result, pay a lot of price .
Conclusion
This topic is not only a fact, it is true in our real world. Many such cases can be seen for this lightning strike.Lighting arresters are usually made of copper and cadmium separate earthing systems are used to operate lighting arresters. These earthing arrangements need to have low resistance and require regular maintenance.
Nowadays most building, offices, Mobile signal towers constructors always mind that this problem and take any prevention for making exclude this problem from system. If he has to count as much money.
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