A switch is a component in electrical device that is used to add or remove power to the device. Switches operate by breaking or establishing an electric circuit in order to affect the power provided to an electrical device. They accomplish this by establishing an electrical circuit in order to turn off the power, and establishing an electrical circuit to turn on power to the device.
One common type of switch is a pressure switch. Pressure switches are switches that operate by making or breaking electrical contact based on pressure. When a certain level of pressure on the switch has been reached, the switch activates to establish or break the electrical circuit. These switches can activate when pressure is added, or when pressure is removed, and turn the circuit on or off when a certain level of pressure has been attained.
Differential pressure switches are a particular type of pressure switch that convert a change in the pressure between two systems into an electrical function. The two systems are constantly monitored, and their relative pressure is measured. When one of the two systems experiences a change in pressure, the change in pressure is compared against a set of differential points. If the change in pressure exceeds the allowable levels, the differential pressure switch activates. If the differential pressure switch was set to off, it will turn on, and if it was set to on, it will turn off.
Differential pressure switches have many different uses, and are common in multiple industries. Some devices that employ differential pressure switches include fuel cells and refrigeration devices.