Why Is the Air Switch Calling an Air Switch? Does It Have Something To Do With Air?

The air switch is one of the electrical components that ordinary users come into contact with the most, so many friends began to wonder: the name is so strange, why is it named "air"?

Air-insulated (that is to say, there is a certain air gap) is called an "air circuit breaker", commonly known as an "air switch". Its arc extinguishing medium is air.

The working principle of the circuit breaker is actually the principle of arc extinguishing. When the circuit breaker opens the circuit, an arc will be generated between the dynamic and static contacts at the moment of opening. Whether the circuit breaker can open the circuit depends on whether the arc generated between the contacts can be extinguished when the circuit is disconnected.

To understand this problem, we must first know the relationship between three terms: switch - circuit breaker - air switch (air circuit breaker).

A switch, anything that can manually break a circuit, can be called a switch. Among the switches, we are most familiar with the wall switches used to control lamps.

A circuit breaker is a type of switch. In the process of opening and closing the circuit, it is easy to ignite – an electric spark, the scientific name is "arc". The arc will damage the switch contacts in light, and hurt people in severe cases, which is a taboo in electrical. Therefore, we need to "extinguish the arc" on the switch, and the switch with arc-extinguishing capability is called a "circuit breaker".

Air switch - circuit breaker is a kind of switch, so an "air switch" is also called an "air circuit breaker". There are many ways to extinguish the arc of the circuit breaker, one of which is to lengthen the arc and let the arc cool naturally in the air until it is extinguished.

An air switch is the cheapest way to extinguish the arc, there is no one. But it is not omnipotent. For example, the voltage of some circuits is relatively high, and the arc generated is very large, so the air switch cannot be used.

So, in addition to the air switch, there are many ways to extinguish the arc. For example, vacuum arc extinguishing (vacuum switch) is to let the contacts directly contact in a vacuum environment, without air, it is impossible to generate an arc at all. For example, the oil immersion switch uses cooling oil to wrap the arc to achieve the purpose of cooling and so on.

The air switch and the leakage switch have the same commonality: they are both switches.

The difference between the air switch and the leakage switch: the air switch will trip only when a short circuit accident or fault occurs, while the leakage protection switch will only trip when the person is electrocuted. The capacity of the air switch can be large or small, and the capacity of the leakage protection switch is not easy to be enlarged, generally single-phase is the majority.

The principle of the air switch and the leakage switch is different, the structure is even more different, and it is absolutely irreplaceable.