Circuit breakers are fundamental components in modern electrical systems, designed to protect circuits and equipment from faults such as overloads and short circuits. Among the various types available, air circuit breakers (ACB) and disjoncteurs à vide (VCB) are widely used in different voltage ranges and applications. Understanding the difference between air circuit breaker and vacuum circuit breaker is essential for selecting the right protection device, especially in industrial and commercial environments where performance, reliability, and maintenance requirements vary greatly.
En savoir plus : Qu'est-ce qu'un disjoncteur à vide en électricité ?
An air circuit breaker, often referred to as ACB, is a type of electrical switchgear used primarily in low-voltage electrical systems. It operates by using air as the arc extinguishing medium. When the circuit detects a fault, the ACB separates the electrical contacts, creating an arc that is cooled and extinguished by air flowing through arc chutes. These breakers are commonly rated for use in systems with voltages up to 690 volts and are popular in low-voltage switchboards, industrial distribution panels, and large commercial installations.
ACBs typically feature robust construction and include both main and arcing contacts, with the arcing contacts designed to handle the stress of arc formation and interruption. Their design allows them to offer reliable protection against short circuits, overloads, and ground faults. Although effective, air circuit breakers generally require more space and regular maintenance due to the mechanical nature of their components and the wear on arc chutes.
A disjoncteur à vide, or VCB, is engineered to handle medium voltage applications and uses a vacuum as the medium for extinguishing electrical arcs. Inside the VCB, the arc forms between contacts enclosed in a sealed vacuum interrupter. The lack of any air or gas inside the vacuum chamber prevents ionization, allowing the arc to extinguish quickly when the current passes through zero.
Vacuum circuit breakers are typically rated for voltages ranging from 11 kV to 33 kV and are preferred in power stations, substations, and industrial facilities requiring high-performance switchgear. The sealed nature of the vacuum interrupter ensures minimal maintenance over the device’s lifespan, and the compact design makes VCBs suitable for indoor and metal-clad switchgear applications. Their efficient arc extinction properties also enhance safety and reduce the risk of fire or explosion.
| Aspect | Air Circuit Breaker (ACB) | Vacuum Circuit Breaker (VCB) |
|---|---|---|
| Voltage Rating | Suitable for low voltage applications (up to 690V) | Suitable for medium voltage applications (11kV to 33kV) |
| Arc Quenching Medium | Uses air as the arc quenching medium | Uses vacuum as the arc quenching medium |
| Arc Interruption | Arc is stretched, cooled, and split using arc chutes | Arc is extinguished rapidly due to vacuum’s high dielectric strength |
| Maintenance | Requires regular maintenance of contacts and arc chutes | Low maintenance due to sealed vacuum interrupter |
| Size and Weight | Larger and heavier due to complex internal components | More compact and lighter in design |
| Operating Environment | Performs best in clean, indoor environments | Suitable for harsh or dusty environments |
| Breaking Capacity | Adequate for low voltage systems | Higher breaking capacity for medium voltage systems |
| Refilling or Replacement | No refilling required; uses ambient air | Vacuum interrupter must be replaced if vacuum is lost |
The difference between air circuit breaker and disjoncteur à vide lies in several key aspects that influence their suitability for different applications.
Air circuit breakers are designed for low-voltage systems, usually up to 690 volts, making them suitable for residential and commercial low-tension distribution networks. Vacuum circuit breakers, on the other hand, are used in medium-voltage systems, typically operating between 11 kV and 33 kV, which makes them ideal for high-demand industrial and utility applications.
In an ACB, air acts as the medium to extinguish the arc formed during circuit interruption. This process involves air ionization and the use of arc chutes to split and cool the arc. VCBs use a high vacuum to suppress and extinguish the arc, leveraging the vacuum’s high dielectric strength and absence of ionizable particles for fast and clean arc interruption.
The arc in an ACB is drawn into an arc chute where it is cooled and extinguished by stretching and splitting. In contrast, the VCB’s arc interruption occurs in a vacuum chamber where the arc is naturally extinguished as the current passes through zero, thanks to the lack of ionized particles and the rapid recovery of dielectric strength.
ACBs require regular maintenance due to the mechanical wear of their components, particularly the arc chutes and contacts. VCBs have a sealed construction with minimal moving parts inside the vacuum interrupter, significantly reducing the need for maintenance and offering a longer service life.
Air circuit breakers are generally bulkier and heavier due to their larger arc control mechanisms and need for ventilation. Disjoncteurs à vide are more compact and lightweight, making them easier to install in space-constrained environments such as indoor switchgear rooms.
ACBs are typically suitable for indoor environments with stable temperatures and minimal dust or moisture. VCBs, with their sealed interrupters, perform well in harsher or more demanding conditions and are less affected by environmental factors, providing more flexibility in installation.
While both types can handle significant fault currents, VCBs offer superior breaking capacity for medium-voltage systems. Their ability to interrupt arcs quickly and reliably makes them ideal for systems with high short-circuit levels.
Air circuit breakers use the ambient air, so there is no need for refilling. In disjoncteurs à vide, once the vacuum interrupter loses its integrity, it cannot be refilled and must be replaced. This process is straightforward and infrequent due to the durability of modern interrupters.
Air circuit breakers are favored for low-voltage systems due to their cost-effectiveness, accessibility, and ease of installation. However, they tend to be larger, require more maintenance, and are less efficient at arc interruption compared to vacuum alternatives.
Disjoncteurs à vide offer outstanding performance in medium-voltage environments, featuring fast arc extinction, low maintenance, and a compact footprint. The primary disadvantage is their higher initial cost, especially in applications requiring custom specifications or higher current ratings.
For medium-voltage applications, disjoncteurs à vide are the clear choice due to their fast arc extinction, low maintenance, and long service life. They offer reliable performance in harsh environments and fit well in compact, indoor switchgear setups. While air circuit breakers are used at lower voltages, VCBs deliver superior safety and efficiency for higher voltage systems, making them the ideal solution for modern electrical protection needs.
Choosing the right circuit breaker is vital for ensuring electrical safety and system reliability. Disjoncteurs à vide stand out with their superior arc extinguishing capabilities, low maintenance, and long lifespan, especially in medium-voltage applications. Chuanli offers a comprehensive range of high-quality vacuum circuit breakers designed for both intérieur et extérieur use. Whether your project requires robust protection in controlled environments or challenging outdoor conditions, Chuanli’s VCB solutions provide dependable performance tailored to your needs. Trust Chuanli for advanced, reliable, and efficient vacuum circuit breakers that keep your electrical systems safe and running smoothly.
