Figure 2. A separable connection includes a housing, contact, and contact plating.
Contact Basics
The purpose of the contact is to establish and maintain a reliable, yet separable low-resistance
connection. There are four major characteristics to this:
Electrical
Mechanical
Thermal
Environmental
Electrically, the contact exerts some manner of spring force to achieve the normal force
required to achieve the low resistance. Mechanically, the contact must exert sufficient spring
force to maintain normal forces long term. Depending on the application, the spring force must
accommodate vibrations and other mechanical disturbances. The interface and bulk contact
must be properly sized to stay cool for the rated current it will carry. To keep the interface
resistance low, the contact's surface must resist the formation of nonconductive films,
corrosion, and other effects.
