The power grid systems in coastal areas of Southeast Asia such as Vietnam and Thailand face triple erosion of high salt fog, strong humidity and direct ultraviolet radiation all year round, and traditional ceramic insulation equipment frequently fails in long-term operation. In response to this challenge, Transocean Power's TUV-certified drop-out fuses and moisture-proof lightning arresters have become a more reliable alternative, and their long-term stability has been verified through actual projects.
The salt fog generated in the coastal environment can penetrate and cause a conductive layer to form on the surface of ceramic insulators, causing flashover or breakdown. For example, data before the transformation of the Da Nang power grid in Vietnam showed that the failure rate of ceramic lightning arresters reached 15% after three years of service in the coastal area, and due to their heavy weight (an average of more than 8kg per piece), replacement requires power outages, and maintenance costs remain high. The high temperature and high humidity environment accelerates the rusting of metal parts, further reducing the mechanical action reliability of the fuse.
Polymer lightning arresters are the first choice for coastal corrosion protection. The silicone rubber shell of polymer lightning arresters is hydrophobic, which can block the adhesion of salt fog, and its hydrophobic migration characteristics make the surface dirt easily washed away by rainwater. Comparative tests show that the life of polymer lightning arresters in salt spray environments is more than twice that of ceramic materials, and the weight is reduced by 40%, and the installation efficiency is increased by 50%. Taking the Da Nang project in Vietnam as an example, after 500 ceramic lightning arresters were replaced with polymer units, the lightning trip rate dropped by 65%, and there were no corrosion failures for 18 months.
In view of the need to meet the dual standards of moisture-proof and safety coordination in coastal environments, the 15 kV TUV-certified drop-out fuse of Transocean Power is very suitable for coastal working conditions. It uses composite insulators (silicone rubber + polymer concrete base) and passes the GB/T 15166.1-2008 and DL/T 402-2010 salt spray resistance tests. The sealing component can block moisture from invading the fuse tube; the fuse has a built-in step-by-step exhaust arc extinguishing system, and is equipped with an alloy casting bracket to ensure that the fuse action is not delayed under high humidity, and the short-circuit breaking capacity reaches 12.5kA58. At the same time, an inclined anti-fall protection frame and a snap-on rain cover are installed to prevent the fuse tube from getting wet or falling and injuring people.
In 2022, the annual failure rate of the original ceramic lightning arrester in Da Nang power grid was 15%, and the maintenance cost accounted for 24% of the total project expenditure. After the upgrade, the combination of polymer lightning arrester + 15 kV moisture-proof fuse was adopted, which reduced the lightning failure by 65% and the fuse action success rate reached 100%;There were no cases of rust or refusal to operate in 18 months, and the maintenance cost was reduced by 30%.
In 2021, a power plant urgently purchased moisture-proof lightning arresters from Transoceanic Power for replacement due to the batch rust of lightning arresters caused by its coastal location. The project requires that the equipment pass the 72-hour salt spray resistance test and withstand an environment with an annual average humidity of 85% after installation. No insulation failure occurred within 2 years after delivery.
Yueyang Power's lightning arresters and 15 kV outdoor drop-out fuses are both TUV certified. The fuses meet the rated voltage of 15 kV, the breaking current of 12.5 kA, the mechanical life of ≥ 2000 times, and can operate stably in an environment of -30℃ to 40℃. No capacity reduction is required within an altitude of 1000m, and they have passed the salt spray test and rain test.
The key to low-cost moisture-proofing lies in preventive design. Data from the Vietnam project show that the combination of polymer lightning arresters and moisture-proof fuses can reduce the total maintenance cost of coastal power grids by 31% in 20 years. This is not only a material upgrade, but also a systematic solution to the corrosive environment.