From: Terry Blanton
Could it be that the crests (towers) are predominantly one polarity and the troughs are the other? If that is true, the massive energy is flowing through the stay cables of the bridge. Notice the lights on the stay cables. How could they survive? Good point. Assuming the wiring for the lighting is fairly well insulated from direct shorting, which it would have to be in a salty environment - then we must ask how much cross inductance is possible? This gets back to amp-turns, no? There would be lots of amps but few turns in the "current path" of the lightning surge, so inductance to the lamps could be less than expected. The big support cable should heat up noticeably however. That in itself is worrisome, since this bridge is a senior citizen. It would be instructive to know if the lights experienced a strong surge in brightness. and how many, if any, failed. Most lighting of this kind in this area is sodium vapor - which can withstand massive surges, since there is no filament at all. San Francisco is one of those so-called "liberal" localities - where public "light pollution" is a real issue overriding lowest cost- and sodium lamps are favored for this - but I do not know for a fact that these are of that type (however they do look to be "sodium yellow" in the image) J.
