Wiring duct,Cable Gland,Cable Tie,Terminals,RCCN

First, the ground line introduction
01 Function
(1) reduce the chance of lightning directly hitting the wire;
(2) The ground wire is generally directly directly grounded, and it relies on a low grounding resistance to induce lightning current to reduce the lightning overvoltage;
(3) The shielding of the ground wire to the wire and the coupling effect of the wire and the ground wire to reduce the lightning overvoltage;
(4) In the case of wire breakage, the ground wire plays a certain supporting role for the tower;
(5) Some insulated ground wires are also used for communication, and sometimes for melting ice.
02 Type
Galvanized steel stranded wire, aluminum clad steel stranded wire, aluminum clad steel stranded wire, steel core aluminum clad steel stranded wire and optical fiber composite overhead ground wire.
Second, the selection of guidelines and requirements
01 Selection principle
(1) According to the lightning protection design and engineering technical requirements, and select the ground wire according to the requirements of wire matching and thermal stability;
(2) The selection of OPGW must first meet the requirements of line lightning protection and its own anti-lightning, and should meet the requirements of optical fiber communication.
02 Ground wire selection technical requirements
(1) galvanized steel strands should be used when there are no special requirements;
(2) When the short-circuit current is increased, the steel core aluminum stranded wire or the aluminum-clad steel stranded wire should be used;
(3) The aluminum-clad steel stranded wire should be used in the severely corroded areas;
(4) The sag shall meet the requirements of the design regulations;
(5) Reliable anti-vibration measures must also be taken for selection.
Third, design selection
1. The ground wire should meet the requirements of electrical and mechanical use conditions, and galvanized steel stranded wire or composite stranded wire can be used. When checking the short-circuit heat stability, the allowable temperature of the ground wire: steel core aluminum stranded wire and steel core aluminum alloy stranded wire can adopt +200 °C; steel core aluminum-clad steel stranded wire (including aluminum-clad steel stranded wire) can adopt +300 °C The galvanized steel strand can be used at +400 °C. The calculation time and the corresponding short-circuit current value should be determined according to the system conditions.
2. The selection of the safety factor of the ground wire should be reasonable, economical and mutually compatible according to the relevant requirements of the design regulations.