Question 114Electricity/Electronics - 1st Asst/Chief70% to pass
When a self-excited DC generator's field has lost its residual magnetism due to a prolonged idle period, it will fail to produce a voltage. Flashing the field is the procedure used to restore the residual magnetism. Using a 12 volt storage battery, how is this performed?
AI Explanation
The correct answer is C.
To restore the residual magnetism in a self-excited DC generator whose field has lost its magnetism, the field windings (F1 and F2 leads) need to be connected to a 12V battery. By connecting the F1 lead to the positive terminal and the F2 lead to the negative terminal of the battery, a current will flow through the field windings, re-magnetizing the field and allowing the generator to produce a voltage.
The other options are incorrect because they involve connecting the wrong leads to the battery terminals, which would not effectively restore the residual magnetism in the generator's field.
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