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Coal igniting 22kV OHL
- Thread starter Padlock01
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oldfieldguy
Electrical
Years ago I worked in a carbon black plant.
If you're not familiar with carbon black, it's pure amorphous carbon and before processing for shipment, it makes baby powder feel like blasting sand. The fine dust gets everywhere. It was not unusual to open a lighting panel and see little sparkles of arcing as electricity tracked across the thin layer of dust.
One of my compatriots saw this phenomenon and thought it might be a good idea to blow the dust out of the panel using compressed air. That's when he learned about an air-dust explosion. He was okay. It wrecked the panel.
old field guy
If you're not familiar with carbon black, it's pure amorphous carbon and before processing for shipment, it makes baby powder feel like blasting sand. The fine dust gets everywhere. It was not unusual to open a lighting panel and see little sparkles of arcing as electricity tracked across the thin layer of dust.
One of my compatriots saw this phenomenon and thought it might be a good idea to blow the dust out of the panel using compressed air. That's when he learned about an air-dust explosion. He was okay. It wrecked the panel.
old field guy
Compositepro
Chemical
Carbon fiber is worse than the dust. The filaments are less than ten micron in diameter (25 microns is 0.001") and will float like spider webs in a breeze. At 120 volts there is just a small flash or sparkle. When the filaments contact 480 volts, the arc is self-sustaining and will trip breakers in feeder panels.
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