33. Electrical degradation of connectors resulting from 

 stress cracks developing in plastic-bodied connectors 

 during manufacture or in service. 



34. Failure of threads in plastic-bodied connectors due 

 to in-service handling. 



35. Plastic plug coupling ring failure due to impace forces 

 in service handling. 



36. Excessive molding flash in rubber connectors in the 

 plug-to-receptacle seal areas resulting in seal failure. 



37. Variation in durometer hardness and/or fit between molded 

 rubber plug and receptacles, resulting in seal failure. 



38. Seal failure of all molded rubber connectors following 

 mating and unmating in arctic conditions. 



39. Pin contact damage at installation or in service due 



to inadequate protection provided by the receptacle shell. 



40. Socket contacts improperly positioned in plug insulator, 

 preventing proper electrical contact with the pin contact. 



41. Wear through of the cable jacket due to improper support 

 on the vehicle resulting in flooding of the harness. 



42. Improper crimping of the contact to the conductor result- 

 ing in an eventual open circuit. 



43. Improper termination of braided shields resulting in 

 braid ends piercing conductor insulation. 



44. Plug-to-receptacle seal failure due to use of improperly 

 sized 0-rings. 



The list above identifies 44 common causes of connector failure. 

 The result of any of these failures is the loss of one or all circuit 

 functions. Figure V-l shows the effect of connector reliabilities if 

 multiple connectors are required for overall system performance. Today 

 deep sea equipment such as the DOTIPOS, Seafloor Deep Corer, or surveil- 

 lance arrays may use as many as a hundred or more connectors. Each of 

 these connector/ cable assemblies and particularly the main electro- 

 mechanical support cable must function to make the system operable. It 

 is shown in Figure V-l that a deep sea system containing only 40 connec- 

 tors would have an overall reliability of 98 percent if each connector 

 had a 99.95 percent inherent reliability. Actually, the reliability of 

 today's deep ocean connectors probably does not exceed 99.0 percent and 

 from Figure V-l a system with 40 connectors would have a reliability, at 

 best, of 80 percent. If 200 connectors were used in the system the 

 overall reliability would be less than 10 percent. 



Manufacturers 



The matrix given in Table V-l indicates the types of connectors made 

 by the various U. S. manufacturers. Table V-l provides identification of 

 available connectors for 13 U. S. manufacturers. 



48 



