Motor/Generator 3: Close-up view of the commutator

The commutator is a rotary switch that reverses the direction of the current every half rotation. The red wire coming from the coil is soldered to the left side of the commutator. The blue wire coming from the coil is soldered to the right side of commutator. As the commutator rotates, the top brush (the flat copper contact) first connects to the left and then the right side of the commutator. Likewise, the bottom brush connects alternately to the right and then the left side of the commutator.

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