Taking the power distribution system as a reference, surges can be divided into two types: external and internal. Statistics show that external surges mainly originate from lightning and other system impacts, accounting for approximately 20%; internal surges mainly originate from the impact of internal electrical loads, accounting for approximately 80%.
Types of Surges and Effective Measures
External surges are pulse-like surges, as shown in the figure below. This type of surge mainly originates from outside the system and is characterized by a very high instantaneous peak value, rising from hundreds of volts to 20,000 volts within a few microseconds. Based on this phenomenon, we employ threshold suppression network technology to suppress surges exceeding a fixed value on the sinusoidal peak voltage. This is an effective and widely applicable solution for protecting electrical equipment, particularly effective against high-energy pulse-like surges generated externally.
Internal surges are oscillating surges, as shown in the figure below. This type of surge is characterized by rising from hundreds of volts to 6000 volts within a few microseconds to milliseconds. Based on this characteristic, we employ active tracking network technology. The surge suppression envelope changes with the sine wave, making it most effective against internally generated oscillating surges. It can quickly detect surges and confine them within the sine wave envelope.
Surge Protection Process
Standard surge protectors deliver current from the power outlet to multiple electrical and electronic devices plugged into the power board. If a surge or spike occurs, causing the voltage to exceed acceptable levels, the surge protector diverts the excess current to the power outlet's ground wire.
Most common surge protectors contain a component called a Metal Oxide Varistor (MOV) to divert excess voltage. As shown in the diagram, the MOV connects the live wire and the ground wire together.
The MOV consists of three parts: a metal oxide material in the middle, and two semiconductors connecting the power and ground wires.
These semiconductors possess variable resistance that changes with voltage. When the voltage is below a certain value, the movement of electrons in the semiconductor generates extremely high resistance.
A surge, also called a transient voltage spike, is an instantaneous overvoltage exceeding the normal operating voltage. Essentially, a surge is a violent pulse occurring within a fraction of a second. Potential causes of surges include heavy equipment, short circuits, power switching, or large engines. Products containing surge protection devices can effectively absorb sudden, enormous energy to protect connected equipment from damage. Surge protectors, also called lightning arresters, are electronic devices that provide safety protection for various electronic devices, instruments, and communication lines. When a surge current or voltage spike suddenly occurs in an electrical circuit or communication line due to external interference, the surge protector can conduct and divert the current in a very short time, thereby preventing damage to other equipment in the circuit.
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Shaanxi West Power Tongzhong Electrical Co., Ltd.
Shaanxi West Power Tongzhong Electrical Co., Ltd. is a leading manufacturer with over 20 years of experience, specializing in high quality 7 to 40.5kV vacuum circuit breakers, switchgears, and a wide range of electrical products. Our advanced manufacturing process ensures reliable, durable solutions, especially our VTZ series vacuum circuit breakers, which are maintenance-free for up to 20 years. With a team of expert technicians, we excel in R&D, manufacturing, and after-sales service for both high and low voltage equipment, delivering excellence at every stage.
Shaanxi West Power Tongzhong Electrical Co., Ltd.
Contact: Ms.Grace Liu (Director of Sales Department)
Email:xdtz04@westpowerelectric.com
Mobile: +86 18091765882(WhatsApp/Wechat/telegram)
Website:https://www.xdtzelectrical.com
