How To Choose A Surge Protector? Professional Explanation Of Two Types Of Lightning Arresters: Power Supply Spd And Network Spd

How to choose a surge protector? Professional explanation of two types of lightning arresters: power SPD and network SPD. When companies choose different SPDs according to their different usage scenarios, they often find that the quality of SPD products on the market varies, and they don’t know how to choose. The reason is that the SPDs on the market are of varying quality, and some cannot even pass the acceptance. So how do we choose a good SPD?

How to choose a surge protection device? Professional explanation of two types of lightning arresters: power SPD and network SPD. The selection of power SPD depends on the following 5 points:

1. Shell: The shell of a high-quality power SPD generally uses PA66 high flame retardant insulation material, which is flame retardant and high temperature resistant. The flame retardant grade is V0 and the temperature resistance is 220 degrees.

2. Internal connectors: Good-performance connectors are made of copper, while inferior products are generally made of steel, which can be seen from the conductivity.

3. Encapsulation material: Power SPDs with excellent performance are encapsulated with imported flame-retardant and heat-insulating silicone or epoxy resin materials. Because the failure mode of the varistor is short circuit when it fails, the varistor heats up. Our goal is to quickly transfer the heat to the low-temperature solder joints here, so that the low-temperature solder joints can be disconnected, thereby cutting off the live wire and the neutral wire. Some inferior products are encapsulated with cement. This kind of SPD installed on the line will never break and will not play any protective role.

4. Trip protection: A reasonably structured power SPD generally uses 145-degree lead-free low-temperature solder, which can gain a few tenths of a second more time for the protection circuit than ordinary 260-degree solder products, and can effectively protect the safety of the terminal equipment.

5. Varistor: The 34*34 varistor valve plate is more able to meet the requirements of the lightning protection level than the Ø25 valve plate.

How to choose a surge protective device? Professional explanation of two types of lightning arresters: power SPD and network SPD. The selection of network SPD depends on the following three points:

1. The combination of lightning arrester and power distribution system

Before choosing a network lightning arrester, you must first be familiar with your own power distribution system. Is your power distribution system TT, TN or IT? After the power distribution system is determined, you can determine your wiring method, as well as whether it is single-phase or three-phase electricity, etc. Then you can find a suitable lightning protection device.

2. Determine the quality of the internal components of the product

Among network lightning arresters, the most core component is the varistor. This material is made of zinc oxide. It has very high production requirements and very high production process standards. When it is struck by lightning, whether it can achieve normal protection is the most critical. So it is very important to know what manufacturer this varistor comes from and whether it is imported.

3. Several parameters for selecting network lightning arresters

First consider the nominal voltage, which needs to be consistent with the voltage of the protected equipment. There is also the rated voltage of the equipment, that is, the voltage that is stable at both ends of the equipment for a long time. Working at this voltage for a long time will not damage the components. The maximum discharge current of the equipment is used to determine the maximum current peak it can withstand