The cable is manufactured according to GB9330 88, IEC227 and JSC258C 1986. It is suitable to used in the line system with AC rated voltage of 450/750V and up to and including 600/1000V for controlling L.V. power supply signal, protecting and measuring. It applies especially to the centerlines of power station and substation up to and including 500KV. The interference from outside electromagnetic field can be suppressed by using thee plastic insulated special shielded control cable.