Walking in the streets of the city road, the most familiar thing is the alternating flashing of various traffic lights. Traffic in the flashing traffic lights in the regular forward and pause. The traffic signal light erected on the pillar of the intersection is to give timely instructions to the traffic. Due to its high erection position, it is easy to damage the indicator light by direct lightning strike. The power line is introduced by the signal controller, but no signal wire. There is a threat of direct lightning strike and power line overvoltage. Therefore, direct lightning strike overvoltage and power line overvoltage are taken as the key points of protection.
The pillar of traffic signal lamp shall be erected, and the current limiting lightning rod shall be installed for direct lightning protection. The top of the bracket and the base of the current limiting lightning rod shall be reliably connected electrically and mechanically, and the bracket itself shall be used for grounding or 40 kV shall be used for grounding 40 × The 40 flat steel is connected with the grounding grid of the bracket itself, and the grounding resistance is required to be less than 4 ohm. The over-voltage protector shall be used for power protection at the power lead of traffic signal lamp and signal controller, and attention shall be paid to water-proof, moisture-proof and dust-proof. The over-voltage protector shall be connected to the grounding electrode of the gantry with multiple strands of copper wire no less than 25 mm, and the grounding resistance shall be less than 4 ohm.
Grounding protection: for a standard intersection, the distribution of pillars and front-end equipment is relatively scattered, so it is difficult to realize single point grounding. In order to ensure the working grounding of equipment and personal protection grounding, only the vertical grounding body is welded into a network structure under each pillar, that is, multi-point grounding, which is mainly aimed at the lightning protection requirements such as step-by-step discharge of incoming waves. In order to ensure personal safety, the grounding body should be more than 3m away from the sidewalk.