Issue link: https://te.mouser.com/i/1410848
Spring properties and normal force are mainly a function of the base contact material. Plating over the base material guards against corrosion and other environmental deterioration. Electrical Concerns The two most fundamental electrical criteria for any connector system are the voltage and current level. Traditionally, anything 1 amp or less and under 10°C temperature rise is considered a signal connector. Signal contacts typically have one or two contact interfaces and often incorporate gold plating for the lowest possible interface resistance. Due to tight contact spacings, signal connectors are not well suited to higher voltage applications (typically >48 volts) due to voltage separation requirements so they remain relegated to low-voltage applications. Although signal contacts have an inherent low current rating, higher currents can be carried through these connectors by using multiple contact positions in parallel; however, the manufacturer should be contacted to obtain the appropriate derating factors for the contacts when paralleled. Similarly, higher voltage ratings are sometimes obtained by skip-loading contacts—that is populating every third or fourth contact position to increase the distance between contacts. Power contacts can be characterized as having current ratings greater than 1 amp and greater than 10°C temperature rise in use. Power connectors are typically larger and have fewer contacts since adequate contact material is needed to carry current without significant joule heating of the contact body. Multiple contact interface points are desirable since they provide parallel paths that serve to minimize interface resistance and decrease joule heating at the interface. Since power contacts usually can handle higher voltages, contacts must be spaced further apart to meet agency dielectric withstand voltage requirements and also provide protection against inadvertent contact. Contact Materials The contacts used in a connector system are at the heart of what makes a connector work. Proper material selection for the end application is always challenging as it is a compromise between cost, mechanical performance, electrical performance, and physical size constraints. Correct material selection is critical to be sure adequate normal force is retained at the interface during the life of the connector. Most contacts use a copper alloy. Brass, an alloy of copper and zinc, is arguably the most common material, finding use in appliance, consumer, HVAC, lighting, personal computing, and other similar applications. Brass contacts can be found in both medium pitch signal and power contact applications. Brass is a good balance between cost, conductivity (set forth as a percentage of International Annealed Copper Standard, which expresses the conductivity of an