Multiple lengths of cable are connected together to form a continuous length. These connections are called joints or splices. If underground ducts are used, the splices are normally completed in a manhole. When a cable is cut, in preparation for splicing or for any other reason, it must be protected from moisture and dirt. Cable ends exposed to the atmosphere will collect moisture and contamination and so should be properly sealed at all times except during the period when the splice is being completed or the cable termination is being installed. Cable ends should be thoroughly inspected before they are trained into final position for splicing.

If the splices are to be completed in a manhole, the cables and the splices should be supported on racks mounted on the manhole wall as illustrated in Chap. 29. The joint or splice is supported between two brackets located on the central portion of the manhole wall. Because of expansion and contraction of the cables, caused by changes in cable temperature, it is necessary to provide reverse curves or offset bends in the portion of the cable in the manhole. These reverse curves enable the cable to take up the expansion and contraction movements without cracking or buckling of the insulation or lead sheath. Therefore, the training of cables on the manhole wall is not only for making a neat arrangement in the manhole but more importantly for providing the expansion space needed to absorb the movements of the cable.

In general, the...