What is a sealed vacuum circuit breaker?

2026-07-27

sealed vacuum circuit breaker

The sealed vacuum circuit breaker is a new generation of medium voltage switching equipment with full insulation and sealed design. The sealed vacuum circuit breaker is manufactured using APG's advanced epoxy resin casting technology. The vacuum arcing chamber, current-carrying circuits, connecting elements and other main current-carrying parts of the sealed vacuum circuit breaker are simultaneously cast into a single sealed pole. Unlike traditional open vacuum circuit breakers, a sealed vacuum circuit breaker does not use air insulation. All high voltage live parts of the sealed vacuum circuit breaker are completely coated with epoxy resin. The sealed vacuum circuit breaker is equipped with a spring operating mechanism, which ensures stable switching on and off, as well as short circuit and overload protection.

Working principle of sealed vacuum circuit breaker

The electric arc is extinguished by a vacuum arc extinguishing chamber of a sealed vacuum circuit breaker. During normal operation of the circuit, the equipment is in the on state. If an overload, short circuit or other fault occurs in the network, the mechanism quickly turns off the circuit. In a vacuum environment, the electric arc quickly extinguishes, the current of the damaged line is switched off, providing protection for transformers, distribution cabinets, cables and other electrical equipment.

Design feature of the product: the arc-extinguishing chamber and high-voltage current-carrying conductors are completely sealed, so the operation of the hermetically sealed vacuum circuit breaker is slightly dependent on external conditions. This reduces the likelihood of contamination, moisture, current leakage on the surface and breakdowns characteristic of traditional switching devices.

Main performance characteristics of hermetically sealed vacuum circuit breaker

Fully sealed sealed vacuum circuit breaker for use in harsh environments

The sealed vacuum circuit breaker's epoxy resin design provides protection against dust, moisture, condensation, salt spray and corrosion. The equipment is suitable for use in mining enterprises, chemical plants, coastal areas and industrial facilities with high dust and humidity. The design reduces the risk of short circuits caused by small animals, suitable for various engineering projects in different countries.

Increased safety and stability of the insulating properties of the sealed vacuum circuit breaker

The sealed vacuum circuit breaker's sealed design optimizes creepage distances and electrical clearances, improving insulation between phases and to ground. The likelihood of electrical breakdown, surface discharge and current leakage during operation is reduced, and maintenance loads are reduced. The equipment is used at substations without permanent presence of personnel and important energy infrastructure facilities.

Compact design of hermetically sealed vacuum circuit breaker to save space in control cabinets

The insulating properties of epoxy resin are higher than those of air. This makes it possible to reduce the distance between the poles of a sealed vacuum circuit breaker and reduce the dimensions of the equipment. Manufacturers of complete switchgears can use smaller cabinets, reduce material consumption for the manufacture of enclosures and reduce transport costs. The product is compatible with compact medium-drawout and stationary distribution cabinets.

Reduced maintenance requirements of the sealed vacuum circuit breaker and low failure rate

The main operating parts of the sealed vacuum circuit breaker are completely sealed, so they do not accumulate dirt, moisture and oxidation are eliminated. Regular cleaning of insulating elements and frequent scheduled inspections are not required. The equipment has a long service life, operating costs are minimal, and is suitable for large export projects.

High mechanical strength of the sealed vacuum circuit breaker, resistance to transportation and vibration

The single design of the sealed vacuum circuit breaker, obtained by casting, is durable, resistant to vibrations and mechanical loads, and not subject to deformation. The product maintains its integrity during road and sea transportation and is in demand for deliveries to facilities in the Middle East, Africa, Southeast Asia and other regions.

Comparison of sealed vacuum circuit breaker and open vacuum circuit breakers

In traditional open vacuum circuit breakers, the arc chute is located in an open space and the insulation is carried out by air. During prolonged use, dust accumulates on the surface, moisture and condensation are possible. Requires regular cleaning and maintenance and is more likely to malfunction in harsh environments. The sealed vacuum circuit breaker has a fully enclosed insulation design, which reduces the influence of the external environment on the operation of the sealed vacuum circuit breaker. The stability, safety and service life of the sealed vacuum circuit breaker have been significantly improved. This type of switching devices based on a sealed vacuum circuit breaker is a current direction for modernizing medium-voltage equipment. With the expansion of renewable energy projects, increasing infrastructure construction around the world and improving energy security standards, the demand for sealed vacuum circuit breaker is growing. Reduced maintenance costs, good insulating properties, stable operation and resistance to harsh operating conditions make the sealed vacuum circuit breaker a sought-after solution for medium-voltage distribution networks. They are gradually replacing open models in many international engineering projects.

Learn more about the products：

🔗 Smart high voltage disconnector 12-252 kV - 6 reasons to choose a new model (qetyandex.cn)

🔗Sealed Vacuum Circuit Breaker: 5 Important Performance Features (qetyandex.cn)

No. Next