Issue link: https://te.mouser.com/i/1410848
Commandments" developed by Jim Whitley at AMP Incorporated (now TE Connectivity) over a half century ago still ring true today: 1. Tin-coated contacts should be mechanically stable in the mated condition 2. Tin-coated contacts need at least 100 grams contact normal force 3. Tin-coated contacts need lubrication 4. Tin coating is not recommended for continuous service at high temperatures 5. The choice of plated, reflowed, hot air leveled, or hot tin dipped coatings does not strongly affect the electrical performance of tin or tin alloy coated contacts 6. Electroplated tin coatings should be at least 100 microinches thick 7. Mating tin-coated contacts to gold-coated contacts is not recommended 8. Sliding or wiping action during contact engagement is recommended with tin-coated contacts 9. Tin-coated contacts should not be used to make or break current 10. Tin-coated contacts can be used under dry circuit or low level conditions Housings The connector housing provides a number of very important functions. Fundamentally, the housing provides electrical insulation between adjacent contacts and between the contact and the outside world. This insulation is usually verified and stated as a voltage in the Dielectric Withstand Voltage (DWV) rating for the connector. A properly designed housing further holds the contacts in one half of a connector in correct relationship with the contacts in the mating half to provide trouble-free mating and unmating. The housing also fixes the spacing between contacts and defines the creep (electrical tracking distance over surfaces) and clearance (linear "line-of-sight" distance) between contacts. In some instances, the housing provides different cavity configurations to allow a mix of signal and power contacts. In yet other applications, connector housings are integrated with a larger circuit enclosure providing an added value to the customer. Lastly, the housing provides some level of environmental protection to the electrical contacts. Environmental Concerns The environmental protection provided by the housing can encompass preventing contaminates (both solid and liquid) from getting into the connector interface and also preventing inadvertent physical contact with the electrical contacts. To prevent interface contamination, various sealing techniques are used. In sealed connectors, the housing, in conjunction with various sealing devices, serves to prevent contaminants from entering into the contact area. Electrical connector housing sealing levels typically adhere to the well-recognized IP levels (Figure 6). EN 60529 outlines an international classification system for the sealing effectiveness against both objects (tools, dust, fingers) and moisture. This classification system uses the letters IP (for