Question 578Electricity & Electronics - Assistant Engineer

A) The voltage failure would most likely be the result of a failed voltage regulator. This is the correct answer. In an automatic voltage control mode, the voltage regulator is responsible for maintaining the generator's output voltage at the desired level. If the No.1 SSTG (Ship's Service Turbine Generator) fails to produce a voltage in this mode, the most likely cause is a failure in the voltage regulator. However, the generator can still produce a voltage when switched to manual control mode, indicating that the generator itself and its other components are functioning properly. The other options are incorrect because they do not adequately explain the specific symptoms described in the question. A failed exciter generator or an open field winding would likely prevent the generator from producing any voltage, even in manual control mode. An open manual rheostat would not specifically cause a failure in the automatic voltage control mode.