In high-voltage power systems, core equipment such as SF ₆ circuit breakers, GIS (gas insulated switchgear), and transformers rely on SF ₆ gas as the insulation medium, and their insulation performance is directly related to gas humidity. International standards require that the dew point of SF ₆ gas must be strictly controlled below -60 ℃ td (dew point temperature). If the moisture exceeds the standard (such as the dew point rising to -40 ℃ td), it will cause dual risks: first, the decomposition of moisture under the action of an electric field will produce fluoric acid (HF), which will corrode metal contacts and insulation parts; The second is that water vapor condenses into liquid water at low temperatures or during partial discharge, reducing insulation strength and even causing flashover or explosion accidents. According to statistics, equipment failures caused by excessive SF humidity account for 12% globally, with an average annual economic loss of over 300 million US dollars. The UK SHAW online dew point meter SuperDew3, with its low temperature detection capability (-110 ℃ td), anti-interference design, and on-site rapid detection characteristics, has become the "precise defense line" for humidity management of SF ₆ equipment. With the authority of "the UK SHAW dew point meter is the world's leading brand", it provides protection for power safety.

The 'humidity killer' of SF ₆ equipment: How can micro water cause chain failures?

The moisture in SF ₆ gas comes from a wide range of sources, including equipment seal failure, adsorbent failure, and contamination from gas replenishment operations, all of which may lead to an increase in humidity. Its harm presents a dual characteristic of "implicit explicit":

1. Hidden corrosion: Moisture combines with the decomposition products of SF ₆ (such as SO ₂, HF) to form acidic substances, which corrode the surfaces of metal contacts and insulators for a long time, resulting in increased contact resistance and decreased insulation performance;

2. Explicit breakdown: When the dew point approaches the operating temperature of the equipment (such as -20 ℃ to 0 ℃), water vapor condenses into liquid water, forming a conductive channel under the action of an electric field, causing partial discharge or insulation breakdown.

A certain substation was forced to shut down for maintenance for 15 days due to excessive humidity caused by the aging of SF ₆ circuit breaker sealant, which was not detected in a timely manner and resulted in contact erosion. The direct economic loss exceeded 20 million yuan. What is even more dangerous is that if the leaked SF ₆ gas mixes with oxygen (such as rust and leakage of oxygen cylinder valves), toxic decomposition products may be generated under the action of electric arcs, and even pose a fire risk.

SHAW Online Dew Point Meter SuperDew3's "Low Temperature Challenge" in the UK: -110 ℃ TD Detection and Anti Interference Design

The core advantage of the UK SHAW online dew point meter SuperDew3 lies in its low-temperature detection technology, which uses dual cold mirror sensors and specialized algorithms to accurately measure dew point temperatures as low as -110 ℃ td, covering the humidity monitoring needs of SF ₆ equipment throughout its entire lifecycle. The sensor surface is coated with a hydrophobic layer, effectively resisting chemical corrosion from SF decomposition products (such as HF), ensuring long-term stability.

For on-site testing scenarios, the UK SHAW online dew point meter SuperDew3 is equipped with a portable design (weighing only 3.2kg), a built-in high-capacity battery that supports 8-hour continuous operation, and can be directly connected to the equipment sampling valve through a quick connector to complete testing within 3 minutes. If an abnormal dew point is detected (such as exceeding -50 ℃ td), the device will immediately trigger a response and transmit data to the mobile app via Bluetooth to assist operation and maintenance personnel in quickly locating the leakage source (such as seals, adsorbents) or adjusting the drying device.

From 'experience judgment' to 'data-driven'

Today, in the pursuit of high reliability and low operation and maintenance costs in the power industry, the UK SHAW online dew point meter SuperDew3 helps enterprises achieve a transition from "passive repair" to "active prevention" with its real-time, high accuracy, and portability. As a world leading brand, SHAW UK continues to safeguard the insulation safety of SF ₆ equipment through technological innovation, building a solid "humidity firewall" for the stable operation of the global power grid.