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| Electric Mine Hoist, Tonopah, Nevada |
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| Electric Mine Hoist Pulleys, Tonopah, Nevada |
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| Westinghouse resistance grids from a mine hoist, displayed at the Tonopah Mining Museum. |
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| Coal empties descend Mullan Pass at Birdseye, Montana |
Whether its decelerating mine hoists or coal trains, engineers have used banks of resistance grids for years, even in my own field of Information Technology. A portable trailer full of them was pulled up to my old office building in Portland, Oregon on a Saturday for testing. They were hooked up to our emergency diesel generator and you should have heard what sounded like howling dynamic brakes just blocks from Pioneer Square.
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| Dynamic Brake Hatch - MRL SD45 |
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| Dynamic Brake Resistor Grids - MRL SD45 |
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| Dynamic Brake Resistor Grids - MRL SD45 |
