WEBVTT

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DC motor with brush on the oscilloscope

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The tension is unidirectional, only the smoothing is perfectible ...

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... with more regularity on my part!

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By reversing the direction of rotation, the polarity is reversed!

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Why tension is unidirectional (same sense)?

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The collector, via the fixed carbon brushes

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switches between tabs so as to maintain the current direction

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This type of rotary switching was used on very old rectifiers

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Some materials only arc-weld continuously

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Zoom on the striated collector

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Graphite brushes and therefore maintenance!

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The collector also is hollowed out by wear

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It was necessary to scratch the graphite residues between the tongues (cct)