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Conic electrical grounding theory states that systematic electrical bonding and grounding applied outward from a vertex sited at the earth ( or other conductive point) will create a strong grounding cone of protection (GCP) that isolates and shields the space within its boundary from the flux of electrical and magnetic currents, affording protection from dangers and annoyances commonly manifested as interference, flashover, electrical shock, and fire. The GCP begins weak with gaps in coverage until it is made more complete with improvements in bonding, grounding, and shielding.
There exists a primary GCP that begins on the supply side of the electrical power service entrance (ESE) at all facilities served with electrical power. The primary GCP relates to the exterior of a facility away from the occupancy. It is often supported by secondary and tertiary GCPs found on the load side of the ESE.
The GCP serves to funnel, or channel, a current flow exchange between the facility and the Earth. Taken together, all grounding cones of protection stack inside one another and strengthen the entire GCP model. Grounding cones of protection are designated as primary, secondary, and tertiary, based on the number of vertex points created away from the grounding electrode system.
The facility grounding electrode system (GES) acts as the vertex of the primary grounding cone of protection from which extends outward and upward a cone of balanced, same-voltage shielding.
GCP extends upward and outward from the vertex to the base, which serves as the upper boundary. More than one GCP is common at a facility.
At a given facility, all separate GCP vertex points, or vertices, will have a direct electrical connection to each other that traces back to the primary GCP and GES. Without such a direct electrical connection, the GCP model will collapse and invite harm to occupants indoors. This negates the functionality of a grounding cone of protection.
A primary GCP is customarily the outermost GCP at a facility. It has the GES as its vertex, and the facility roof as its base.
Roofing and wall materials are commonly not conductive, so gaps within the primary GCP are to be acknowledged and mitigated by thorough pre-construction planning if more complete protection is desired. For example, a lightning protection system or conductive materials at the roof or exterior walls could be used in the construction and affirmatively bonded to the primary GCP.
An exterior integrated systems bonding point commonly rides the primary GCP between the ESE and GES.
A tertiary GCP is commonly found indoors and may begin its vertex at a multilink power outlet strip that includes grounded AC power and telphone or cable television receptacles as well. An indoor ISBP, such as a proxy node, is an example of a tertiary GCP vertex.
Conic electrical grounding theory introduces the grounding cone of protection (GCP), which has gaps at its base and along its exterior. The cone is inherently weak and requires strengthening through systematic electrical bonding and grounding in order to reduce hazards.
The grounding electrode system acts as the vertex of a facility's primary grounding cone of protection.
Secondary and tertiary GCPs exist further within the primary GCP. These extend and strengthen the primary GCP at a facility, thereby maximizing electrical and fire safety for all occupants.
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