Appendix 

 ALTERNATE WET CONNECTOR CONCEPTS 



In preparation for the prototype wet connector design another review was made of the existing connector 

 techniques. A summary of the various methods for making electrical contact underwater follows: 



Method Manufacturers/Developers 



Pin types (utilizing wiping seals) Naval Civil Engineering Laboratory (NCEL) 



Mare Island Naval Shipyard (MINSY) 

 Commercial 



Diaphragm puncture Commercial 



Grease displacement Commercial 



Split transformer Commercial 



Compression wiping (button contacts) None 



Figure A-1 shows the general appearance and relative size of these other wet connectors. 



The Mare Island Naval Shipyard connector [2] is a 440-volt power connector with a successful 

 experimental model already in existence. It was designed specifically for use by divers with submarines and is 

 small and light to handle. It would require fabrication of a mating guide mechanism to be compatible with a 

 manipulator. It is somewhat complex, and is not designed for heavy mechanical loads. 



Most commercial pin-wiping power connectors are quite small and inexpensive but operate at power levels 

 far below those required for major structural applications. They require considerable force to mate and are not 

 now adapted for use by manipulators. The materials used are not suitable for direct application to high voltage 

 and degrade unacceptably with extended submergence. 



The commercial diaphragm-puncture connector operates at up to 600 volts, has eight contacts, and is very 

 simple. It is between the NCEL and MINSY connectors in size and capacity and is the only right-angle power 

 connector found. It is mated by set-screws. This connector combines many of the features required for 

 structural applications but has not been tested for higher voltages or deep submergence. 



One company uses a grease-filled connector for automatic connection of submersible pumps. The con- 

 nector configuration is different from most in that the contacts are in line rather than in parallel, so that the 

 connectors are insensitive to rotational alignment. The contacts are simply concentric rings spaced along the 

 male pin and female cylinder respectively. This offers a much easier mating arrangement, especially for remote 

 operations. Unfortunately the concept is still experimental and has not been adapted for use in the ocean 

 environment. The exposed grease surface is particularly vulnerable to contamination. 



Split-transformer and related electromagnetic coupling techniques are normally not applicable to high 

 power connectors because of the large size and weight of transformers of kilowatt capacity. There are several 

 commercial products which use this concept for coaxial and other signal applications, however, and the extreme 

 simplicity and reliability of the mating operation make this method very attractive for further development. 



Analysis of these designs and the experience gained from each of them indicated that the pin-types were 

 best suited to high-voltage, deep-submergence use. The success of the mechanical portions of the Mare Island 

 Naval Shipyard design indicated that their experience would be of value in the development program, so a small 

 contract was awarded to determine the feasibility of scaling up the 440-volt design to the NCEL high-power 



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