The difference between surge protector and arrester

1. In terms of application field, it can be divided into voltage level.
The rated voltage of the arrester ranges from <3kV to 1000kV, low voltage 0.28kV, 0.5kV.
The rated voltage of the surge protector is less than 1.2kV, 380, 220~10V~5V.

2. Different protection objects
Lightning arresters protect electrical equipment, while SPD surge protectors are generally used to protect secondary signal circuits or to power supply circuits at the end of electronic instruments and meters.

3. Different insulation level or withstand voltage level
The withstand voltage level of electrical equipment and electronic equipment is not in the same order of magnitude, and the residual voltage of the overvoltage protection device should match the withstand voltage level of the protected object.

4. Different installation positions
Lightning arresters are generally installed on the primary system to prevent the direct intrusion of lightning waves and protect overhead lines and electrical equipment; SPD surge protectors are mostly installed on the secondary system, after the lightning arrester eliminates the direct intrusion of lightning waves, or lightning arresters There is no supplementary measure when the lightning wave is eliminated; therefore, the lightning arrester is mostly installed at the incoming line; the SPD is mostly installed at the end outlet or signal circuit.

5. Different flow capacity
Because the main function of lightning arrester is to prevent lightning overvoltage, its relative current capacity is relatively large; for electronic equipment, its insulation level is much smaller than that of electrical equipment in the general sense, so SPD is required to protect against lightning overvoltage and operating overvoltage. But its flow capacity is generally not large. (SPD is generally at the end and will not be directly connected to the overhead line. After the upper level of current limiting, the lightning current has been limited to a lower value, so that the SPD with a small current capacity can completely protect it. Value is not important, what is important is residual pressure.)

6. There are also big differences in other insulation levels and focus on parameters.

7. Surge protectors are suitable for fine protection of low-voltage power supply systems, and various corresponding specifications can be selected according to different AC and DC power supplies. The power surge protector has a large distance between the terminal equipment and the previous surge protector, which makes it easy to generate oscillating overvoltage or induce other overvoltages on the line. It is suitable for the fine power surge protection of terminal equipment, and the protection effect is better when used in conjunction with the front-level surge protector.

8. Different materials
The main material of lightning arrester is mostly zinc oxide (a kind of metal oxide varistor), and the main material of surge protector is different according to the anti-surge grade and graded protection (IEC61312), and the design is better than ordinary The mine is much more precise.

9. Technically speaking, the arrester cannot reach the level of a surge protector in terms of response time, pressure limiting effect, comprehensive protection effect, and anti-aging characteristics.

From the nominal discharge current:
The discharge current In of the arrester index ranges from 1.5kV, 2.5kV, 5kV, 10kV, 20kV. The nominal lightning current of 8/20us, the nominal discharge current of the surge protector is from 5kA, 10kA, 0.5kA, 20kA, 30, 20, 120kV.

Fourth, the test standards and requirements are very different
Since the lightning arrester is connected to the electrical primary system, it must have sufficient external insulation performance, and the appearance size is relatively large, while the surge protector is connected to a low voltage, and the size can be made small. For example, in terms of appearance and volume, the arrester is mainly made of silicone rubber , Ceramics, iron cans, large volume, heavy weight surge protector with a small amount of silica gel, epoxy package, plastic shell, metal and ceramics, metal and plastic.

Using place
Lightning arresters are mainly used in power stations, lines, distribution stations, power generation, capacitors, motors, transformers, neutral points, steelmaking, and railways. Surge protectors are mainly used in low-voltage power distribution, cabinets, low-voltage electrical appliances, communications, signals, machine stations, and computer rooms.