By Chuck Cooley, Hicks Lightning Protection; Ponder, Texas
As technology advances and facilities have more and more sensitive electronic equipment, the potential increases dramatically, with the possibility that a structure and/or its electronic equipment will be damaged from an induced surge. There are a few ways a facility can be affected by an induced surge/current i.e. lightning strike. These surges can wreak havoc on electrical components and other electronic devices. The first of these induced surges or currents would be from a direct lightning strike. A typical lightning strike is approximately 30kA and 300 million volts1. The second way a facility may see an induced surge would be from the transmission lines. These transmission lines would be struck by lightning and the induced current would travel along those lines and potentially travel into the facility, damaging electronic equipment. The third would be from a remote lightning strike, whereas the surge would travel through the Earth, and if there are any underground cables or utility services, the surge/current could travel back into the facility, again damaging electronic equipment and machinery.
Point #1 – Capture the lightning strike: This is done by having a conventional (Franklin) lightning rod system installed on the building (Fig 1). We want to make sure that the lightning protection system is the preferred point of contact in the event of a lightning strike. This system is to be installed to the national standards of NFPA 780, UL96A, and LPI175. It is also important to note, this system is to be installed by a certified lightning protection contractor, who is a member of UL and the Lightning Protection Institute. After the installation is completed, it is highly recommended the system be inspected by a third party (UL or LPI) and given a UL Master Label or an LPI Master Installation Certificate.
The next portion of this article will focus on the various points or areas one needs to apply to help protect their structure and internal electronics from being damage from any stray induced currents
By incorporating these six points, the chances of any stray induced currents will be greatly reduced. Proper grounding and bonding is the backbone of any electrical protection system and having a low resistance grounding system is key. These steps are not only beneficial for the structure and its electrical components, but it’s also beneficial for personnel safety.
To learn more about facility lightning protection and safety, or to find a lightning protection contractor in your area, contact the Lightning Protection Institute or visit www.lightning.org. RF
