Correlation is not Causation

• On Average there are 60 Thunderstorms per Year in Illinois. [80 in Southern Illinois]
• That means [60/365] 1/6 of the time that an electronic device fails it will be during a Thunderstorm.

Evidence of Lightning Damage

• Evidence of High Voltage Surge (e.g. flashovers at terminals and relay gaps)
• High voltage damage to a capacitor (usually “run” capacitor)
• Verification of high voltage surge with powerr company
• High voltage damage to delicate circuit boards
• In motors – evidence that winding is grounded out. (usually run vs. start winding)

Lightning Damage Photos