How about the lightning protection (SPD) effect in the Small Power Distribution Board?
It's the lightning season again. In recent days, the author has constantly received calls from friends who reported that household appliances were damaged by lightning. They are very anxious and eager for me to help them solve the problem of lightning protection （SPD). After all, the loss of being struck by lightning once is too great. Some friends mentioned lightning protection （SPD), and the media publicized its lightning protection （SPD) effect is not bad. So, is this so-called lightning protection （SPD) useful?
The Small Power Distribution Board factory will popularize the knowledge of lightning protection （SPD).
1、 Principle of lightning protection （SPD)
As we all know, when lightning weather occurs, although lightning rarely acts directly on houses or electrical appliances, the huge electric energy of lightning will form induction lightning on electrical appliances and other metals. It is a huge instantaneous voltage, which can break down and burn electrical appliances in an instant. lightning protection （SPD) forms an infinite impedance by installing a transient voltage absorber such as a lightning tube or a varistor between the input lines. When the induced lightning produces a transient voltage, the resistor will quickly reduce and transfer the transient energy, so as to achieve the effect of protecting the internal electrical equipment.
It can be seen that lightning protection （SPD) can effectively absorb the surge pulse from the power supply system, which is indeed effective for induction lightning, but has no protective effect on direct lightning. To prevent direct lightning strike, lightning rod, grounding wire and other lightning protection （SPD) measures should be taken.
2、 How effective is lightning protection （SPD)
The probability of direct lightning is much lower than that of inductive lightning, and when the lightning rod guides the lightning to the ground, it will also cause inductive lightning in the circuit, so the use of lightning protection （SPD) can effectively make up for the shortcomings of lightning protection （SPD) measures such as lightning rods, and form a reliable protection for the front end of household appliances. Of course, when we decorate and install wall switches, we all require the design and installation of air switches, This is also a protective measure to deal with the sudden change of instantaneous current. It can quickly cut off the circuit when there is instantaneous current, so as to form an effective cooperation with lightning protection （SPD) and protect household appliances from being burned by lightning.
3、 How to prevent household appliances from being struck by lightning
Lightning is a very complex electrical phenomenon, and the current lightning protection （SPD) measures mainly include primary, secondary and tertiary protection. Level I and level II lightning protection （SPD) are measures such as lightning rods and grounding wires, which mainly deal with direct lightning strikes. Level III protection is air switches, lightning protection （SPD) and other protection directly against sudden changes in voltage and current inside the circuit. The three perform their respective duties and work together, so as to comprehensively prevent lightning accidents.
Of course, with these lightning protection （SPD) measures, we can't guarantee 100% lightning protection （SPD), but the probability is already very small. What we need to do is to pay attention to the integrity and good condition of these lightning protection （SPD) facilities at ordinary times. In addition, in case of particularly heavy lightning weather, unplugging the power source plug is the most safe and reliable means.
