Effect of lightning
The effects of lightning on equipment are not limited to the interior of buildings that have been hit directly. A huge electric current flows in a short time, so a large electromagnetic field is generated. This electromagnetic field induces a lightning surge on the metal line. This lightning surge propagates to the equipment connected to the metal line and affects the equipment.
Damage caused by lightning surge
Most of the lightning damage to equipment is caused by the above lightning surge. Below is an example of the damage.
- Failure of electronic devices such as PCs (PCs and multifunction devices in the office cannot be used)
- Home appliances such as water heaters, washing machines, and TVs (it stopped working after a thunderstorm)
- Security camera failure (it stopped working after a thunderstorm)
- Security system failure (the door could not be opened or closed with a card key after a thunderstorm, or the fire alarm broke down)
- System failure in a multi-storey car park (it stopped working after a thunderstorm)
- Telephone or private branch exchange failure (disconnected after thunderstorm)
In this way, lightning surges cause equipment and facilities familiar to us to fail.
Lightning intrusion route
Lightning damage has been increasing due to the recent advanced information technology and the accompanying networking. This is due to the formation of lightning entrances and exits through networking. Devices that were previously free from lightning damage are also covered. On the other hand, many semiconductor devices are used in IT equipment that supports the advanced information society, and because they are miniaturized and mounted at high density, they are vulnerable to abnormal voltage such as lightning. The intrusion route of lightning that affects these electronic devices may be power lines, networks/communication lines, ground lines, space (electromagnetic waves), etc.
Insulation breakdown of equipment
Most of the damage caused by lightning is due to the inflow of electric current due to breakdown of insulation barrier of equipment.
The equipment usually has insulation barrier and can withstand a certain voltage.
When an abnormal voltage such as lightning enters, it cannot be prevented by the insulation barrier, and it penetrates into the equipment, causing damage to the equipment.
Modern society is under threat of lightning surge
Lightning surges can occur anywhere with metal tracks. Even if you look over your home or office, most of the equipment will be connected to some wire. Power line, telephone line, coaxial cable and LAN cable. Lightning surges intrude through these lines and destroy the inside of the equipment.
The driving voltage of information devices such as personal computers has decreased due to power saving. As a result, the surge withstand voltage of the device is also reduced. Therefore, it has a side that it is weak against abnormal voltage due to lightning surge. In particular, network equipment is prone to lightning surge intrusion because the power supply line and communication line form the lightning surge inlet/outlet.
Although it is not possible to prevent the occurrence of lightning surges that cause lightning damage, damage can be reduced if the intrusion of lightning surges can be prevented. Therefore, it is important to prevent the intrusion of lightning surges.