Surge Arrester Seal Failure: How Does Moisture Gradually Cripple Power Facilities?

In the daily operation of power systems, the biggest concern is often sudden lightning strikes, but the "silent killers" lurking inside equipment should not be underestimated. high voltage lightning arrester Poor sealing can lead to moisture absorption. This seemingly minor process defect is often the source of abnormal equipment operation. Once moisture penetrates the sealed cavity, the internal resistor elements change properties under the influence of moisture, disrupting the previously stable insulation balance and directly threatening the safety of the entire line.

The chain reaction after moisture intrusion

After the 33kv lightning arrester equipment gets damp, its internal physical and chemical environment becomes extremely poor. Moisture forms a thin film on the surface of the resistor elements, which generates a continuous leakage current under operating voltage.

• A Significant Increase in Resistive Current: Moisture reduces the insulation level of the resistor elements, potentially doubling or even increasing the previously weak resistive current several times over.

• Valve Plate Performance Deterioration: Prolonged exposure to a humid environment causes irreversible chemical degradation of zinc oxide valve plates.

• Severe Localized Heat Release: Increased current is accompanied by heat accumulation; excessively high localized temperatures can lead to casing rupture or thermal collapse.

Why does the sealing structure fail?

Looking deeper into the equipment structure, if the 10 kv lightning arrester is not properly sealed, it will get damp, mainly due to the details of the connection parts.

Key Issues

Aging of the sealing rings, uneven pressure of the compression springs, or insufficient finishing of the vent at the factory are all major sources of moisture infiltration. Especially during seasonal changes with drastic temperature fluctuations, the internal pressure changes create a "breathing effect," forcibly drawing external moisture into the tank. This structural lapse leaves the internal resistors, which should be dry, constantly soaked in a "sauna."

Early Warning Signals in Operations and Maintenance

Since poor sealing of 11 kv lighting arrester can lead to moisture absorption, how can we detect it in advance? Regular infrared thermal imaging will reveal that the temperature of the faulty phase is significantly higher than the normal phase. Furthermore, abnormal fluctuations in the total current value in the live monitoring data are also distress signals from the equipment. If these issues are not addressed promptly, and the internal insulation completely breaks down, the consequences will be far more severe than just a power outage.