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The residual magnetism of a self excited DC generator is lost. To build up its emf what to be done to regain the residual magnetism?

The residual magnetism of a self excited DC generator is lost. To build up its emf what to be done to regain the residual magnetism? Correct Answer Field winding must be excited by low voltage DC supply

  • Residual magnetism is the small magnetic field left in the iron cores of the shunt fields when the generator is at rest
  • Without it, the fields would have to be flashed with a DC current in order to start the generator generating; Hence to start the generator, it is necessary for the DC shunt generator
  • Once it is destroyed, it can be restored by connecting its field finding to a DC source for a short time to magnetize the poles
  • So, we need to connect the field winding to a battery (DC source)

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