PURPOSE: To enable automation of cable inspection using a robot by holding the quad with an engaging element without confusing its arrangement, thereby enabling electric connection with individual conductive elements.

CONSTITUTION: A pair of engaging elements 25 each consisting of an L-shaped engaging plate 23 and a rod 24 secured thereto are carried by a cylinder mechanism reciprocally longitudinally of the rod 24. By holding the quad 22 with such an engaging element 25, a contact member 26 breaks through the insulator 35 of a cable core 34 and comes into contact with the conductive element 36, enabling electrical connection with a pair of cores on a diagonal line by means of the pair of engaging elements 25.