A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be_____________?
Correct answer: B. about 2 V
- A. zero
- B. about 2 V
- C. about 50 V
- D. 220 V
Explanation
With no field excitation, only residual magnetism produces voltage, so the open-circuit voltage is a small residual value rather than zero or rated voltage. A value of about 2 V is typical in this context.
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