Air circuit breakers are used to protect power lines and electrical equipment from overloads. They also have other functions like ground fault and leakage protection.
They don’t use oil so they require less maintenance. This makes them a great choice for plants that want to avoid fire hazards. Plain air circuit breakers have two pairs of contacts in the shape of horns. There are also magnetic blowout ACBs that extend the arc through a chute of splitters.
Types
Air circuit breakers are available in different types. The plain ACB is the simplest form with main points of contact in the shape of two horns. The arc of these breakers extends from one tip to the other when the contacts are closed. They have a low contact resistance and are made of copper with silver-plated surfaces.
When a fault occurs, the primary contacts of these breakers are separated and current shifts to another contact called an arcing contact. Electromagnetic forces and heat action push this arc upwards. This arc is divided by metallic separation plates called arc chutes to help achieve cooling and also prevent fire. The growing emphasis on sustainable energy sources drives the demand for air circuit breakers in Asia-Pacific. This trend is further driven by the rapid growth of infrastructure projects and commercial buildings. In addition, the increasing digitization of power systems has increased the need for advanced grid infrastructure. This is driving the demand for air circuit breakers that can handle these new power system technologies.
Applications
Air circuit breakers have a wide range of applications in different industries and power distribution systems. They are commonly used to protect power lines and electrical equipment from overcurrents, short circuits, and under-voltage. They are also used to ensure the safety and uninterrupted operation of electrical appliances in homes.
Generally, air circuit breakers are fixed or rackable. They can be operated manually or electrically. The operating mechanism of an air circuit breaker is composed of left and right side panels, contact system, instantaneous overcurrent trip, arc extinguishing mechanisms, and the coils of overvoltage and undervoltage trips. To operate an ACB, atmospheric air acts as a dielectric to push the arc towards insulating lamella, where it is stretched and extinguished by blowout coils linked in series with the circuit being broken. These coils help prevent the arc from reforming after the breaker has opened. Some types of arcs are harder to extinguish than others. For this reason, they require a magnetic field created by the current in the blowout coils to extend it further away from the contacts.
Maintenance
Air circuit breakers tend to require less maintenance than those that run on oil. This is because they do not have the same amount of mechanical stress that other circuit breakers for sale experience.
Despite this fact, it is important that they are inspected on a regular basis to ensure that they continue to work properly. This means a physical inspection of the outside of the unit to look for things like water, rust and evident damage that could prevent it from functioning. Once the inspection is complete, the breaker should be opened to inspect the operating mechanism inside. This should be clean and lubricated as per the manufacturer’s recommendations. A good lubricant will reduce the friction in certain connections which can slow down the operation past safe limits. It will also help to extend the life of the main contacts. It is also important to conduct a variety of electrical tests. This will help you get a better understanding of the condition of your air circuit breakers.