Have you ever blown up a balloon until it popped? Whether you did it for fun or on accident nothing warned you that the balloon was at its limit. If this were to happen with industrial equipment such as an air compressor, it could be disastrous and dangerous. Therefore, air compressor switches are installed to prevent such a catastrophe. The air compressor switch can have more functionality than simply telling the air compressor to stop building pressure inside of the reservoir.
I remember being younger and working in my dad’s garage and hearing this loud noise when he turned on the air compressor and then about 5 minutes later the noise would cease. Only after he used some power tools would the noise start up again. I later found out that the reason the air compressor had a mind of its own was because of a switch that was programmed to adjust the pressure inside of the reservoir accordingly to a predetermined range.
Most air compressor switches are able to both tell when the pressure is low or high in order to start up or shut down. Some additionally detect leaks and drastic pressure drops to issue a warning or shut down until the problem is fixed. The purpose of air compressor switches goes beyond failsafe applications. The main purpose is the keep the reservoir at a pressure that is predetermined by two preset values.
Any air compressor despite the industry it is used in should have a switch in order to keep the compressor functional and safe. They are made of a variety of different types of materials including: aluminum, bronze, acetal, cast iron, zinc, steel and stainless steel. Depending on the switch some may have a display to visualize what is going on in the compressor while others may operate as they were programmed to do.