Contactor Auxiliary Contacts: Ratings and Functions

What is the typical rating for auxiliary contacts in a contactor?

a) Higher amperage than primary contacts

b) Lower amperage than primary contacts

Answer:

b) Lower amperage than primary contacts

Contactor auxiliary contacts are usually rated at a lower amperage than the contactor's primary contacts. This distinction is important because the primary contacts are specifically designed to handle the main current flow, which is typically a higher amperage. On the other hand, auxiliary contacts are primarily used for control signals and lower current loads.

For example, in a contactor that is responsible for controlling a motor, the primary contacts would manage the high current needed to power the motor. In contrast, the auxiliary contacts might be utilized for indicating when the motor is running or as part of a control circuit with lower current requirements.

The lower rating for auxiliary contacts helps to ensure that they do not become damaged or worn out quickly when dealing with lower currents. By having a lower amperage rating, the auxiliary contacts can effectively fulfill their function without being overloaded.