Equipotential Bonding

Equipotential Bonding: A Quick Overview Equipotential bonding is a safety concept used in electrical installations to keep all exposed conductive parts and certain other metal parts at the same electrical potential. The idea is simple: by tying these parts together with conductive connections, any fault that makes one part energized will not create dangerous voltage differences between metal surfaces that a person might touch. Why it matters - A fault can energize metalwork such as taps, pipes, radiators, or appliance casings. If another metal part at a different potential is touched at the same time, the result could be a dangerous electric shock. - Bonding helps ensure fault currents have a low-impedance path to earth. This helps protective devices (like fuses or circuit breakers) operate quickly, isolating the faulty circuit and reducing the risk of electric shock or fire. - It also reduces nuisance voltage differences between metal objects that are likely to be touched simultaneously. Main concepts: main bonding and supplementary bonding - Main bonding: This connects the building’s main earthing arrangement to extraneous conductive parts near the service entrance, helping to keep the entire installation at a similar potential. - Supplementary bonding: This provides additional connections between extraneous conductive parts in areas with higher shock risk (for example, in certain wet zones or multi-point metalwork). The exact needs for supplementary bonding vary by country, region, and the specific installation. Where you’ll typically see bonding - Water and gas pipes that are metallic. - Metal heating system components, central heating pipes, and radiators. - Exposed metalwork in or near kitchens, bathrooms, and utility rooms. - Metallic structural parts and enclosures that could become energized during a fault. - In many modern codes, bathrooms and other wet areas have special rules about bonding to manage touch potentials safely. How it’s done (high level) - A bonding conductor (a copper wire of appropriate size) is connected from the main earthing point to each designated extraneous conductive part so they share the same potential. - All connections are designed to be durable and corrosion-resistant, with robust terminal connections to avoid loosening over time. - The work is performed in accordance with local electrical codes and by a qualified electrician to ensure correct sizing, routing, and protection against damage. Important notes - Regulations and terminology vary by country (for example, main bonding, protective bonding, and supplementary bonding may be defined differently). Always refer to the local electrical code and a licensed electrician. - Bonding is part of overall electrical safety. It complements proper grounding, circuit protection, and safe installation practices. - Do not attempt to modify bonding or electrical systems yourself. If you have concerns about bonding in an existing installation, arrange a professional assessment. In short, equipotential bonding helps keep metal parts at the same potential, reducing shock risk and helping protective devices do their job more reliably. It’s a key safety concept in modern electrical installations.