A Guide to Calculating Telecommunications Bonding Conductor (TBC) Size for Data Center Design

Proper grounding and bonding are essential for safety, performance, and regulatory compliance in any data center. One critical component in this system is the Telecommunications Bonding Conductor (TBC)—a conductor that plays a central role in connecting telecommunications infrastructure to the grounding system.

What Determines the TBC Size?

The appropriate size of a TBC is determined based on:

Maximum fault current the system might experience

Length of the conductor (affecting voltage drop)

Acceptable voltage drop to maintain system performance and safety

Applicable standards and local electrical codes

Accurate sizing is essential to ensure low impedance paths to ground, minimize electromagnetic interference (EMI), and protect both personnel and equipment.

Latest Standards to Reference

To ensure proper sizing and system reliability, always consult the most current industry standards, such as:

ANSI/TIA-607-D – Generic Telecommunications Bonding and Grounding (Earthing) for Customer Premises

ANSI/BICSI 002-2024 – Data Center Design and Implementation Best Practices

NECA/BICSI 607 – Standard for Telecommunications Bonding and Grounding Planning

ISO/IEC 30129:2023 – Telecommunications Bonding Networks for Buildings and Other Structures

These standards provide detailed requirements for conductor sizes, bonding conductor routing, interconnection methods, and acceptable resistance levels.

Design Tip

For most modern data centers, a minimum conductor size of 6 AWG (American Wire Gauge) is common for TBCs; however, larger sizes may be necessary based on fault current and installation conditions. Ensure bonding conductors are properly labeled, routed without sharp bends, and securely bonded to all required telecommunications grounding elements.

Why It Matters

Correctly sizing and installing the TBC not only meets compliance but also enhances the safety, reliability, and uptime of critical data center systems. Poor bonding and grounding can result in equipment failures, data corruption, or dangerous voltage potentials.

Need support designing your data center’s bonding and grounding system? The Northern Link team is here to help with expert insights and compliant solutions.