Telecom Grounding Calculator

Calculate grounding requirements for telecommunications installations.

Expected maximum fault current

Grounding Conductor Sizing (TIA-607)

Application Min Copper Notes
Equipment Bonding#6 AWGMin per TIA-607
Rack Bonding#6 AWGTo TGB
TGB to TMGB3/0 AWGMax 50 ft
Backbone (TBB)3/0 AWGBetween TGBs
Tower/Antenna#2 AWGLightning protection

Telecom Grounding Standards

TIA-607 Requirements

  • TMGB: Telecommunications Main Grounding Busbar
  • TGB: Telecommunications Grounding Busbar
  • TBB: Telecommunications Bonding Backbone
  • Max resistance: 25 ohms to earth (5 ohms preferred)

Best Practices

  • Single-point ground reference
  • Star topology from TMGB
  • Minimize conductor lengths
  • Use exothermic welds for permanent connections
  • Test ground resistance annually