What application commonly uses Form C contacts?

Form C contacts are often used in applications that require the ability to switch between two different circuits, making them particularly suited for electrical relays and switches. This configuration allows the contacts to serve either as normally closed (NC) or normally open (NO); thus, it can connect to circuits in a way that either completes or interrupts the flow of electricity, depending on the control signal received.

In essence, Form C contacts enable versatile switching capabilities that can be utilized in various applications, particularly where the control of multiple load states is crucial. This makes them ideal for relays and switches, which are designed to operate loads safely and effectively while adapting to different operational needs. Other options may represent specific applications of switching or protection but do not capture the versatility and functionality provided by Form C contacts as efficiently as relays and switches do.