Question 503Electricity/Electronics - Assistant Engineer70% to pass
When a self-excited alternator'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 D) The F+ and F- leads are disconnected from the alternator field. The F+ lead is connected to the positive terminal of the battery, and the F- lead is connected to the negative terminal.
This is the correct procedure for flashing the field to restore the residual magnetism in a self-excited alternator. By applying a voltage from the battery across the field windings (F+ to positive, F- to negative), a current is induced that remagnetizes the field, allowing the alternator to start producing voltage again.
The other options are incorrect because they either involve the wrong leads (S+ and S- instead of F+ and F-), or they connect the leads in the wrong polarity, which would not properly restore the residual magnetism.
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