Taking the Mystery out of Equipotential Bonding Requirements For Swimming Pools

To elucidate the difference in grounding and bonding to me, a sage mogul once used the analogy of a marriage. He defined that “grounding and bonding are like a wedding ceremony… Then after a short time, the husband gets grounded! ” While this tale (if not solely true) was entertaining, it did nothing to take the mystery out of grounding and bonding for me. Perhaps nowhere in the Code is this thriller more prevalent than at 680.26 coping with equipotential bonding for swimming swimming pools and similar installations. I would nominate this NEC part as one of the vital misunderstood and misinterpreted sections in the entire Code. Historically, this part is one of those who go through a few of probably the most dramatic revisions from Code cycle to Code cycle. In this article, we are going to try to take the “mystery” out of this one space for equipotential bonding for swimming pools and related installations.

Bonding necessities are an necessary and distinctive protecting method employed to extend the safety of the customers of bodies of water corresponding to pools, spas, and scorching tubs. Bonding connects the conductive components of the pool structure, close by metallic objects, and electrical tools enclosures collectively. Bonding is required to remove voltage gradients (rises in voltage potential) in the pool area. When metallic parts are bonded collectively, they successfully get rid of variations of voltage potential that will exist between the individual conductive elements and thus reduce the shock hazard. If these metallic conductive parts aren’t bonded collectively, this leaves these conductive components having the potential of being at completely different voltage potentials. In a case like this, the human body can serve as a “conductor” between two conductive components at completely different voltage potentials if contact is made with these conductive parts. If a conductive path is provided between two conductive elements at different voltage potentials, this current goes to naturally equal itself out between these conductive components.

An electrical shock occurs when the human body is used because the “conductor” between these conductive components. If these conductive parts are mechanically, electrically, and deliberately bonded (married) collectively, there is often no shock hazard present as these conductive parts are all the time at the identical voltage potential. Once known as the “common” bonding grid, it was modified to “equipotential” bonding in the course of the 2005 NEC to help make clear and describe the operate and function of this part. Now is an efficient time to discover the different purposes served by bonding and grounding and to develop a transparent understanding of the 2 terms. Bonding is used to equalize voltage potential variations to reduce shock hazards between totally different parts of the pool by connecting potentially conductive components collectively. Grounding entails providing a low-impedance, floor-fault return path from the tools required to be grounded again to the supply of the electrical system, typically by way of the gear grounding conductor routed with the branch-circuit conductors. This path facilitates the operation of the fuse or circuit breaker to permit it to take away the faulted condition.

Briefly, bonding means “connected together,” while grounding means “connected to earth.” Grounding and bonding together provide the safety from shock hazards that’s so important, notably in an aquatic setting comparable to a swimming pool. Since several forms of electrical equipment commonly used with swimming pools, sizzling tubs or spas that are bonded collectively must even be grounded, an interconnection between the grounded (impartial) conductor and bonding grid exists. Swimming pools, spas, and hot tubs present particular shock hazards to people. The water is blended with chemicals, which regularly improve conductivity. Individuals are in direct contact with the water and encounter grounded objects resembling metallic ladders. Electrical equipment is used to circulate and heat the water and for other related features such as illumination. The Code necessities, if rigorously followed, site will reduce the electric shock hazards to a suitable level. One of those measures is the bonding collectively of conductive parts of the pool and steel parts of electrical equipment related to the pool.

The objective is to provide a technique of equalizing the voltage potential of all tools and elements. If completed correctly, there will be no current stream between these components that can be dangerous to personnel. The required bonding is achieved by connecting all of the elements collectively by an adequately sized and correctly related sequence of copper bonding conductor(s) or other acknowledged bonding methods. The Code describes the fundamental bonding requirements and provides an inventory of gadgets required to be bonded together. 1. All steel elements of the pool construction, including the reinforcing metal of the pool shell, coping stones and deck. The same old steel tie wires are considered appropriate for bonding the reinforcing steel together, and welding, brazing or special clamping just isn’t required. These tie wires should be made tight. Reinforcing steel successfully insulated by an encapsulating, nonconductive compound at the time of manufacture shouldn’t be required to be bonded.