Everything24: What You Need to Know About Lightning Protection Systems

Worldwide, there are about 40 to 50 lightning strikes per second, or about one and a half billion a year. Not only is the amount of strikes alarming, but each strike can also range from 100 million to 1 billion volts and receive billions upon billions of watts.

Such voltages and frequencies cause irreparable personal injury and property damage as well as unforeseen equipment downtime, costly replacements and breaks in production schedules.

Lightning strikes may never be part of the program, but the defense should be created for your benefit, including a lightning protection system.

In this post, we provide an overview of lightning protection system measures and the steps required to reduce the risk posed by lightning.

Who Needs a Lightning Protection System?

There is no known way to prevent lightning. The purpose of a lightning protection system is, therefore, to control the discharge in a way that prevents personal injury or property damage.

Architects, designers, developers and engineers should evaluate the need to protect at an early stage of the structural design. Although no strict rules can be given, it is possible to use detailed guidelines to reach the required degree of protection.

Common issues to consider include the level of hazardous lightning, workers, equipment, structural damage, and problems resulting from lightning-producing failures.

Although not a rigorous science, evaluating these factors in terms of comparing risk, economy, and aesthetics is one of the trials. The Lightning Protection system Solution Guide provides questions to help you determine the appropriate level of protection for your structure.

What Are the Components of a Lightning Protection System?

The first mention of the traditional lightning rod during the infancy of the lightning protection system was first published in Benjamin Franklin Gentleman's Magazine in 1750. A year later, he recommended using lightning rods to protect houses and other structures from lightning.

Although this varies on a case-by-case basis, Franklin's recognition that the essential point of any advantage is the riskiest of direct lightning still forms the basis of many protection systems today.

However, the fast-moving 250 years see that today's advanced lightning protection systems demand 84% to 99% efficiency depending on the desired level of protection.

Below, we outline the initial steps and related components needed to prevent damage caused by lightning successfully.

1. Intercept the Lightning Flash

As Franklin mentioned, the highest point of any advantage is the riskiest of direct lightning. Lightning rods or air terminals capture the strike at the desired end and help conduct energy to the ground to reduce the risk of damage.

The two keys to useful strike termination devices (i.e. power rods or air terminals) are type and installation.

Air terminal types may be one of the following depending on the application:

Rods - usually copper or aluminum
Masts - can be copper, aluminum, fiberglass or stainless steel.
Mixed conductors (building surface or elevated)
Catenary wires
Natural components

To best capture lightning strikes, the following considerations should be made for the installation of air terminals, often depending on the type of material:

Install as close as possible to the edge of the roof.
They are protected as required.
Select materials to reduce the risk of corrosion.
Do not introduce trip hazards on the roof surface.
Do not look for places where water can flow (e.g. water).
Avoid penetration to the roof to fix the conductor.

For more information on air-termination specification requirements and advice, see the Erico Power Safety Handbook.

2. Conduct the Lightning Current to Earth

The components needed to do this are known as down conductors, which provide the interconnection of air terminations in the earth-termination system.

They usually follow the profile of the structure, without leaving any position where the safety of individuals can be compromised. Down conductors should provide multiple parallel paths for the discharge of electricity from electricity to the ground.

Doing so reduces the risk of current density, thereby reducing the risk of side flashing. This reduces the effects of electromagnetic radiation of the emulsifier current at the internal points of the structure.

In general, down conductor systems should:

Provide multiple paths for power flow.
Be as concise and straightforward as possible.
Stay at a distance and use the rings of equivalent bonding.
Be a direct continuation of the air-termination system.
Will not be installed on guitar or downspouts (even if covered with PVC).
Connect to the Earth End Network through a test.
Equip with external protection to reduce exposure to accidental damage or vandalism.
Equip with three-millimeter, cross-linked polythene insulation where there is a risk of exposure due to the possibility of touch.

There are detailed requirements for type, spacing and more for different buildings, which are available in the Erico Power Protection Handbook.

3. Dissipate Current into the Earth

The reliable functionality of the whole lightning protection system depends on an effective earthing or grounding system.

Consideration must be given to earthing systems:

Providing a less disabled network to isolate fast-growing lightning.
Reducing the risk of touch and action.
The long-term performance of the system - the quality of materials and connections.

Grounding systems can be comprised of:

Ground rods
Perimeter (ring) bare wire
Radials
Ground plates
Concrete (rebar)

4. Create an Equipotential Bond

Removal of voltage gradients requires equipotential bonding, which reduces the likelihood of electric shock or electrical equipment error.

From the air termination system to the grounding system of the conductors, each product must work effectively to effectively transfer the discharge from the barrier to the release - without the risk of people or building.

To achieve overall effectiveness, lightning protection systems must:

Reduce thermal or mechanical damage to the structure.
Avoid sparking, which can cause fire or explosion.
Limited measures and touch voltages to control occupants' risk of injury.
Avoid damage to internal electrical and electronic systems.

Want to Learn More About Lightning and Lightning Protection Systems?

Download our lightning protection system guide to learn the basics of lightning. See if your building structure is on the list, especially at risk of strikes and learn about the specific elements available to break effectively, manage and consume lightning strikes See.

Equip yourself with the knowledge to fully prepare your facility in the event of a lightning storm.

Everything24

Saturday, November 14, 2020

What You Need to Know About Lightning Protection Systems