What Is Grounding Busbar (TGB/TMGB)?_
The grounding busbar, often designated as a Telecommunications Grounding Busbar (TGB) or Telecommunications Main Grounding Busbar (TMGB), is a central bonding point installed in each row or room. It connects to the facility’s main grounding electrode system and serves as the reference point for all equipment and structural bonding within that zone. Proper bonding to the busbar minimizes potential differences and reduces the risk of electrical shock or equipment damage from fault currents or lightning surges.
Technical Details
The busbar is typically made of copper or aluminum, sized per the National Electrical Code and TIA-607 standards, with multiple pre-drilled holes for bolted connections. Bonding conductors from each rack and cable tray are terminated using listed lugs and fasteners, with the busbar itself bonded to the building’s grounding electrode system via a minimum-sized conductor as specified by code. In GPU clusters, the busbar also provides a bonding point for the liquid cooling system’s metallic components to prevent galvanic corrosion and ensure safety.
How Leviathan Systems Works with Grounding Busbar (TGB/TMGB)
During rack assembly and structured cabling, our field crew bonds each rack frame and cable tray to the row’s TGB using a green or bare copper conductor. We verify that the busbar is clearly labeled and that all bonding connections are tight and corrosion-free before commissioning.
Related service
GPU Rack Assembly & Rack-and-Stack →