1. Product Introduction

In the subway grounding system, due to the requirements for fault current protection, the grounding grid is located beneath the structural bottom plate. Therefore, when the electrical equipment at subway platforms is grounded, it must be connected to the grounding via a grounding lead to ensure a reliable grounding system. In the past, grounding leads were typically extracted directly from the structural bottom plate or routed through PVC pipes. This approach often fails to meet the fault current protection requirements and groundwater may溢出 from the grounding leads, failing to meet the design specifications for the subway.

Our research and production of ground outlet devices are specifically designed for the unique requirements of subway grounding. These devices can effectively prevent groundwater seepage when connecting the power equipment grounding, signal equipment grounding, and lightning protection grounding to the comprehensive grounding network, and they also meet the requirements for stray current protection. The YuLong ground outlet device consists of several parts, including a protective tube, a water-stopping ring, grounding outlet wires, and insulating filling materials. The protective tube is made of stainless steel, the grounding outlet wires are made of T2 copper, and the hollow part of the protective tube is filled with insulating material. It boasts scientific material selection, reasonable structure, advanced technology, stable and reliable quality, and convenient construction and installation.

2. Product Precautions

Protective pipe outer surface for grounding lead-out device coated with rust-proof paint

2. The grounding lead-out device's protective tube is elevated 100mm above the ground-level building structure. The reserved length of the grounding lead-out wire is not less than 400mm above the opening of the protective tube.

3. The grounding lead-out device protection pipe passes through the center of the structural bottom plate reinforcement mesh (without contacting the structural reinforcement), and the space between the grounding lead-out wire and the protection pipe is filled with insulating filling material to ensure insulation between the grounding lead-out wire and the structural reinforcement.

4. The location of the grounding lead-out point (leading out from the station structure bottom slab) should be near the cable well in the under-deck of the platform or in the cable tray of the strong/weak electrical equipment room on the platform level, avoiding the track under-channel, structural walls, and tracks, etc. The position of the lead-out point must be confirmed by the relevant professional.

5. Enhance the protection of the grounding lead-out device during construction to prevent mechanical damage and chemical corrosion.

6. The connection between the grounding lead-out wire and the grounding grid is done using heat-fusion welding (exothermic welding).