Zinc oxide arrester is a new type of arrester, it is mainly assembled by zinc oxide valve piece. It has complete protection function, long-term stable operation, and the small size, so it has been widely used in the electrical power system. The zinc oxide surge arrester is also called MOA. They have the following characteristics:
1, Good nonlinear voltammetry characteristics.
Zinc oxide surge arrester has great resistance, and it will be in a good insulation state under normal working voltage. It will be in a low resistance state Under the action of lightning overvoltage. The lightning current is discharged, so that the residual voltage of the electrical equipment in parallel with the surge arrester is limited below the safety value of the equipment. After the harmful overvoltage disappears, the surge arrester will quickly recover high resistance with the insulation state, so as to effectively protect the insulation of the equipment from the damage of the overvoltage.
2, Gapless, small size, light weight.
Gapless surge arrester has no gaps. The residual voltage value is small under the impact discharge voltage of steep wave head, which can reduce the insulation level of power equipment. It is of great economic significance for ultra-high voltage system.
3, Quick action response, good protection performance.
Zinc oxide surge arrester discharge without delay. Once the operating voltage begins to rise, the zno disc immediately begins to absorb the energy of the overvoltage, it will resist the development of the overvoltage.
4, High current capacity.
The current capacity of zinc oxide surge arrester is completely free from the restriction of series gap burn, it can be used to limit operating overvoltage, can also withstand a certain duration of power frequency overvoltage.
5, How to find a good manufacturer of zinc oxide surge arrester?
There are many manufacturers of surge arrester in China. But it is not easy to find a good supplier of surge arrester in China. It is better for you to have a purchase agent in China, the agent will check the factory for you, and they can do the sample test of surge arrester before delivery. Moreover, you please don’t forget to check the following items:
- please check whether they have the production line of zinc oxide varistor blocks. Please don’t purchase the surge arrester from the small factory which has not the zno production line. Some of them will use the second hand zno varistors for your surge arrester, but the surface and appearance of surge arrester are same and beautiful.
- Please check whether they have the high voltage test equipments. Many small factories have not the high voltage test equipments for the surge arrester, for ex, residual voltage impule test for complete surge arrester, not for zno blocks. Some small factories will not do the test of residual voltage on the complete surge arrester, they only do it on the single zno varistor pieces. Changsha rich power group is a large manufacturer of surge arrester in China. We are prdoucing all size of zno varistors by ourself, we can do all routine test on complete surge arresters according to standard. We have a 1000kVA high voltage test cent in our factory.
- Please check whether they have engineer teams, some small factories only do the assemble, so they have not the engnieer team, so their price is very lower.
- please don’t only compare the price of surge arresters, Lower price, lower quality, this is a fact.