tion of useful tables are included. Because 

 the subject of cables is covered exhaustively 

 in the Handbook and references (31) and (36), 

 only a cursory discussion is given herein, and 

 it is taken directly from the above sources. 



As with so many other components of sub- 

 mersibles, the selection of outboard cabling 

 for privately owned vehicles depends both on 

 the designer's personal choice and availabil- 

 ity. Among the options are single insulated 

 conductors, standard commercial cables, oil 

 filled cables, welding cable, metal sheathed 

 cables and hybrid cabling systems. Typical 

 problems encountered include: 



1. Incompatibility of insulation and jacket 

 compounds with pressure-compensating 

 fluids. 



2. Water penetration of cable jackets and 

 molded plug terminations. 



3. Cracking of cable sheath. 



4. Problems of potting plug molding com- 

 pounds to cable jackets and metal shell 

 of plugs. 



5. Conductor breakage at molded plug ter- 

 minations. 



6. Instability of electrical characteristics 

 with change in hydrostatic pressure or 

 with long-time immersion. 



7. Breakage of braided shields under re- 

 peated cable flexing. 



8. Mechanical damage during vehicle serv- 

 icing. 



Mr. D. K. Walsh (35) summed up the situa- 

 tion quite succinctly in a 1966 report to the 

 Marine Technology Society: "Historically, 

 the cable problem has been treated as an 

 afterthought." Walsh proceeded to develop a 

 historical account of cable selection (what- 

 ever seemed adequate), terminations to asso- 

 ciated equipment (trial and error) and the 

 means of connecting equipment to a power 

 source (whatever method came to mind). 

 Tracing the evolution of combining cables 

 and connectors, Walsh described an early 

 approach known as the "Schlumberger 

 Splice" (Fig. 7.31) which worked satisfactor- 

 ily with single conductor cables. From this 

 developed multi-pin, watertight, disconnect 

 type connectors (Fig. 7.32) which are essen- 

 tially throw away units, inexpensive and 

 rugged and still in use today. These rubber 

 molded connectors, according to Walsh, had 

 much to do with combining the cable problem 



C 



Hf 1 



TZIt 



Fig 7 31 The Schlumberger Splice (D K Walsh) 



with the connector problem since a rubber 

 molded connector could only be installed on 

 or molded to a vulcanizable type of cable, 

 e.g., neoprene jacketed. This began the de- 

 sign of what Walsh calls an Engineered Ca- 

 ble System: A combination of a cable with a 

 connector and a suitable junction, for the 

 development of which the systems engineer 

 must have full prior knowledge of the associ- 

 ated connectors and the types of junctions to 

 be employed. Walsh's report contains a num- 

 ber of considerations to insure compatibility 

 and optimum performance and is one of the 

 first (if not the first) contemporary attempts 

 to approach the entire cable/connector prob- 

 lem in a systematized, soundly engineered 

 manner. 



Fig 7 32 A variety of rubber-molded disconnect type connectors (D. K. Walsh) 



353 



