What is surge protective device?

Date:2021-07-16
What is surge protector?
Surge protector, also called lightning protector, is an electronic device that provides safety protection for various electronic equipment, instruments, and communication lines. When a spike current or voltage is suddenly generated in the electrical circuit or communication circuit due to external interference, the surge protector can conduct and shunt in a very short time, so as to prevent the surge from damaging other equipment in the circuit.
Why do we need the surge protector?
Lightning disasters are one of the most serious natural disasters. Every year, there are countless casualties and property losses caused by lightning disasters in the world. With the large-scale application of electronic and microelectronic integrated equipment, there are more and more damages to systems and equipment caused by lightning overvoltages and lightning electromagnetic pulses. Therefore, it is very important to solve the lightning disaster protection problems of buildings and electronic information systems as soon as possible.

With the increasingly stringent requirements of related equipment for lightning protection, the installation of surge protectors to suppress the surge and instantaneous overvoltage on the line, and the overcurrent on the discharge line has become an important part of modern lightning protection technology.

How surge protector works?

The working principle of our product is: when there is no overvoltage, the product is in the off state, and the resistance is infinite. When there is overvoltage in the system, the product is in the closed state and the resistance is infinitely small, and the internal components will clamp the voltage within a certain range.The current flowing through the line will be absorbed and discharged. After the discharge is completed, the product returns to a high resistance state (disconnected state) so that it will not have other effects on the equipment.
What are the important parameters of the surge protector?
1.The max continue operating voltage(Uc): Refers to the maximum effective value of AC voltage or DC voltage that can be continuously applied to the SPD.
2.Max discharge current(Imax):Refers to the maximum discharge current that the SPD can withstand once using an 8/20μs current wave to impact the SPD.
3.Minimun discharge current(In):Refers to the discharge current at which the SPD can work normally
4.Protection level: Maximum value of the voltage between theterminals of the SPD in presence of an impulsive overvoltage.lt is a fundamental parameter to correctly choose the SPD; account of it must be taken in relation to the impulse voltage of the equipment to be protected.
What THOR do?

Since its establishment, Thor has been in compliance with the international lightning protection standard (IEC61643-1) and is committed to the production and research and development of surge protectors. Products include house power surge protectors, photovoltaic surge protectors, industrial surge protectors, and networks surge protectors, signal surge protectors, etc. to provide consumers with better options for lightning protection products.

 

if need more details, feel free to email us: cicely@thorspd.com; Whatsapp number: +8618969702600

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What is surge protective device? | Surge protection device SPD - THOR Electric