Brushes of DC machine are made up of ?

1 Answer

Answer :

Brushes of DC machine are made up of carbon.

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Last Answer : Field coils of DC generator are usually made of copper.

Last Answer : Brushes of D.C. machines are made of carbon.

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Last Answer : Poles of DC machines are laminated to reduce the eddy current losses in the poles.

Last Answer : Copper losses,iron losses,variable losses , constant losees

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Last Answer : Iron loss, copper loss and mechanical losses these are the losses in DC machine.

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Last Answer : Open circuited armature coil of a D.C. machine is identified by the scarring of the commutator segment to which open circuited coil is connected and indicated by a spark completely around the commutator.

Last Answer : In case of D.C. machine winding, number of commutator segments is equal to number of armature coils.

Last Answer : Iron losses in a D.C. machine are independent of variations in load.

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