Summertime in Florida … The lightning capital of the world coupled with storms of the summer heating can be dangerous without proper protection and precautions.  Although there is no iron-clad guarantee against damagegrounding-sign occurring, several things can be done to reduce the risk of a strike.  Lightning protection and electrical grounding go hand in hand to provide the best protection.  All it takes is one direct hit to a poorly protected structure to result in catastrophic damages including fire, structural damage, electrical breakdowns, electronic device failure and substantial loss of revenue during repairs or reconstruction.

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The most important aspects of an effective protection plan are to capture the lightning strike with an air terminal system, conduct the energy to the ground safely though a downconductor, dissipate the energy into a low impedance and low resistance grounding system, bond all ground points to eliminate ground loops and create an equipotential plane.  This type of interdependent system will provide the best protection to equipment from surges and transients on incoming power and telecommunications or signal lines and costly operational downtimes.

The installation of an effective grounding and lightning protection system is not complete without the required testing to ensure the ground resistance levels are appropriate for the facility to be protected.  While there is not a standard ground resistance101_0011 threshold that is recognized by all agencies, the NFPA and IEEE have recommended a ground resistance value of 5.0 ohms or less.  The NEC requires that system impedance to ground is less than 25 ohms.  Large electrical substations generally require the grounding electrode resistance be 1 ohm or less due to the high potential to earth of the electrical system.  Ground resistance measurements are required upon installation and periodically thereafter to ensure continuity of protection.  Some of the factors that can alter the resistance values after installation are facility expansion, addition of computer-controlled equipment, or the installation of nonmetallic pipes or conduits underground.  In addition, the water table is gradually falling in many locations causing the earth electrode systems that were previously effective to end up in dry earth resulting in a rise in resistance. 

Precision Electric of Lakeland can design and implement bonding, grounding and lightning protection systems, perform earth ground resistance testing, or rectify your electrical system vulnerabilities. 

Ensure you’re protected … Call us today for more information or to speak with a project manager about your lightning protection or grounding needs.