Equipotential bonding terminal box wiring frame

An equipotential bonding terminal box connects all exposed conductive parts and metallic structures to a common earth potential, using appropriately sized conductors to minimize potential differences and ensure safety.

Purpose of Equipotential Bonding Terminal Boxes

Equipotential bonding terminal boxes, such as the Delixi CDPE30, are designed to connect electrical devices, exposed metal parts, and building metallic structures (e.g., water pipes, heating pipes, steel reinforcements) to a common grounding system. This reduces the contact voltage risk and prevents dangerous potential differences between conductive parts, protecting both people and equipment from electric shock or fault voltages.

Wiring Principles

Conductor Selection: Use copper or galvanized steel conductors with a cross-section suitable for the installation. For protective equipotential bonding, typical minimum cross-sections are 6 mm² for copper or 16 mm² for aluminum. In industrial control cabinets, a minimum of 16 mm² copper is recommended between cabinets.

Connection Points: Connect all metallic parts, including the terminal box, to the equipotential busbar or main earthing terminal. This includes structural steel, pipework, and other exposed conductive parts. Routing: Route equipotential bonding conductors in parallel with data cables but maintain minimum clearance to avoid interference.

Cable shielding alone is not sufficient for equipotential bonding. Terminal Box Features: Boxes like the CDPE30 have strip holes for flat iron or copper bars and knock-off holes for incoming and outgoing lines, facilitating secure connections to the building's metallic framework.

Installation Tips

Flush Clamping: Clamp data cable shields near the equipotential busbar to maintain grounding continuity. Corrosion Protection: Ensure conductors and terminal box surfaces are protected against corrosion, using electrostatic spraying or other protective coatings. Supplementary Bonding: In sensitive areas, such as medical environments, supplementary equipotential bonding may be required to connect all conductive parts to the main protective earth.

Compliance: Follow relevant standards such as DIN VDE 0100, IEC 61730, and BS EN 62305 for building and PV system installations.

Summary

To wire an equipotential bonding terminal box to a frame: Use properly sized copper or steel conductors. Connect all metallic parts and structural elements to the terminal box. Route conductors carefully, avoiding interference with data cables.

Ensure corrosion protection and compliance with local electrical standards. Verify that all connections maintain continuous equipotential bonding to reduce shock hazards and protect equipment. This approach ensures that the terminal box effectively equalizes potential across all connected metallic parts, providing a safe and reliable grounding system.