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I was also excited when you finally heard from a Florida utility man on the actual reason/cause for the low-side arc. You were right, it was a capacitor bank. I still wonder what the low-side voltage was. My guess is 19.9kV, maybe higher, but for certain, not lower. That arc was too strong for anything lower. The linkbelt crane is still one of the most awesome displays of the power lurking in those overhead lines. THAT is a full-load arc. Note that in one photo the arc is on the left side of the crane, then on the right side. I thought it might have been arcing off the stabilizers on each side on the rear, but the metal wheel on each tire is closer to ground. Still don't know, but seeing the concrete being broken up by that amperage is scary. At 'only' 46,000 volts, that is one unGodly imppresive arc. This spring/summer I was treated to some glorious nite-time light shows during the spring storms that occur here every year. I live in a high rise, and enjoy sitting on my balcony to watch the CG's and 'cloud-crawlers'. As I can look over towards Annadale (VA.) I always see when a CG hits a power line. You see the bright white stroke, immediately after, the sky is filled with a blue-green glow of the arcing powerline it hit. Then part of the lights of the city are gone until the recloser re-engergizes the effected circuit. Often as not, the green glow re-appears, usually now mixed with dull orange as a bushing or other piece of equipment is burned, meaning a permantent fault. And lastly, I was treated to a sight I never saw before. On the intersection of Beuregard and Duke street, there is an intersection of utility lines, large 19.9kV jobs. There is also a very large flock of pigeons that hang around there. Well I happened to be waiting at the traffic light there when this huge flock came in for a landing across all three phases of the line and the wooden poles holding the line. Some unlucky bird (or group) connected the center phase of the line to ground (flapping wings?) The dragon appeared briefly, and over a dozen cooked and smouldering pigeons fell to the ground! I still cannot understand why these birds are able to land on an energized line. Even medium volteges like 4 to 7kV will make corona discharge-to-air which would mildly shock a large bird. 19.9, and even 33.3kV lines around here often harbor perching birds. Why? I DO note that larger lines are never touched by birds at all. Anything new in videos?
Looks to be too quiet here on your message boards. Being the 'geek' I am I still continue to study your videos and photos, as these are still the best on the web.
Looking at that amazing photo of the close positive lightning strike...the fellow who took the photo says that there is a leader in the photo that is only a few meters from where he stood. I don't see one. I see the closest leader in the top of the tree on the right hand side of the photo, had the main arc taken THAT path, the stroke would have been much closer to him, I believe close enough to stun him. The next leader I see is behind the palm tree in the foreground, actually well behind the main stroke. What I DO see is a ghost (possibly reflective inside the camera) image of the actual main stroke, this is just to the right of the palm, and in front of its trunk, 'appearing' directly in front of his position. You can see that the main stroke was actually split, appearing as two strokes when viewing this reflective image.
For sure the venting mist was mineral oil...you can see the cloud ignite from the far side of the transformer to the side facing the camera position. It was ignited by the arc itself, as you can see the smoke suddenly stop and the arc turn bright blue in the mist just before it ignites it. Good stuff.
Take care,
Fred
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