“LGJ” is the symbol of steel cored aluminum strand, in which “L” is the abbreviation of aluminum wire, “G” is the abbreviation of steel core, and “J” is the abbreviation of stranded wire.
240/40 refers to the nominal cross section of the wire is: aluminum 240 mm2, steel 40 mm2; the structure of the wire is aluminum 26, diameter 3.42 mm2, 7 steel, diameter 2.66 mm2; aluminum calculated cross section is 238.85 mm2, the calculated cross section of steel is 38.90 mm2, the total cross section is 277.75 mm2; wire diameter 21.66 mm; conductor DC resistance is not greater than 0.1209Ω / km; rated tensile strength 83370N (Newton); unit mass 964.3kg / km; manufacturing length of 2000 meters; short circuit current and access system location and access system of the equipment and change, must have a complete wiring diagram, can be calculated according to the calculation; line impedance is also set up with the line of different ways, but also according to the drawings can be calculated.
The transmission line of more than 10kV, the China commonly used aluminum clad steel strand (LGJ) as a conductor, which is wrapped with aluminum steel wire, steel wire and wire transfer for current to reduce corona and other losses, according to the different voltage wire cross-section gradually increased. Such as domestic 500kV high voltage transmission line conductors, generally use the LGJ-400/35 the conductor.
