Things You May Not Have Heard About Lightning and Grounds

When we think of grounding systems, we tend to think only of resistance and how resistance can be reduced. But the things we do to lower resistance may increase inductance, which could actually make matters worse, especially for fast-rising secondary surges.

Lightning Induced Ground Potential Rise (GPR)

Select the most suitable waveforms for evaluating equipment resistibility to lightning damage when a GPR is either the suspected source of the damage, or its effects are to be tested for.

Lightning and Miss Liberty

One hundred million volts, more or less. That is the potential that is developed as roiling masses of air and water and ice molecules furiously swap electrons during a thunderstorm. Charge separation, caused by the friction in the air, related to the mechanism of static built up by rubbing balloon on cat, fills the atmosphere with pockets of ions–positive and negative. As the voltages build, the normally-insulating air molecules stress and disassociate and filaments of current crackle across the sky, releasing mega-joules of energy in each stroke. The supersonic expansion of the ionized air along the stroke path, boiled to a plasma, cracks in a sonic boom, rolling across the sky as thunder.