Types of Copper Electrical Contacts

by Kevin Smith Author

Copper is present in almost all electrical applications because of its electrical and thermal conductivity. When it comes to creating electrical contacts, using copper opens many possibilities due to its wide variety of alloys. While some applications need precious metals like gold, silver, and platinum, copper and copper alloys make great cost-efficient alternatives.

Four of the most common copper electrical contacts are arcing contacts, demountable contacts, fixed contacts, and sliding contacts. Each type has its own features, applications, and characteristics.

Arcing Contacts

Arcing contacts are named after how they form an arc when they make or break currents in an electric circuit. This arcing phenomenon happens when an electric current travels to the gap between the contacts. Arcing contacts come in various types including high voltage and high current arcing contacts to low voltage contacts. High voltage and high current arcing contacts are used for transmitting electricity, while low voltage contacts are used in automotive applications.

Demountable Contacts

Demountable contacts are also referred to as non-arcing contacts. As their other name suggests, they don't make or break connections under a load. Meanwhile, they're called demountable because the connections for their applications can remain stationary for years. One key feature of these contacts is their great resistance under stress, which is important for their different applications:

· High power application - power sockets and non-load breaking isolators

· Low power application - multi-way sockets and bulkhead connectors

· Signal and control application - cable connectors and insulation displacement connectors

Fixed Contacts

Fixed contacts are two conjoined components that come in either bolted or crimped contacts. The conjoined components form a single electrical contact that's used in all current ranges and voltages. Fixed contacts also come in various types, which allows them to be used for many applications, from wiring connections of low voltage printed circuit boards to large busbars found in switchgear.

Sliding Contacts

Sliding contacts are named after how they're designed to move either horizontally or vertically without separating. These contacts are required to operate efficiently while in motion or stationary. Sliding contacts have two types, each with different functions for different applications.

The first type of sliding contacts is high speed, heavy current types. These include commutators in motors and generators and pickup contacts used in electric transport.

The second type of sliding contacts is low speed, light current types that are usually made of brass alloys. One example of low speed, light current sliding contact is a potentiometer, which is used to regulate or alter the flow of an electrical circuit.

Copper's natural properties and its wide array of alloys have created different electrical contacts for different applications. Thanks to copper electrical contacts, the need for costly devices is eliminated. Respective industries can achieve desired results with versatile, cost-efficient alternatives.