Question 265Electricity/Electronics - Assistant Engineer70% to pass
Emergency generators are required to automatically start upon a loss of normal supply voltage, according to 46 CFR, Subchapter J (Electrical Engineering). In conducting a test of the emergency generator automatic transfer of load function, if the normal system supply voltage is 450 VAC, to what value would the emergency generator output voltage have to rise to trigger the automatic transfer of emergency loads to the emergency generator?
AI Explanation
The correct answer is C) The voltage would have to rise to a value ranging from any voltages between 382.5 VAC and 427.5 VAC.
This is because according to 46 CFR Subchapter J, the emergency generator output voltage must rise to a value between 85% and 110% of the normal system supply voltage of 450 VAC in order to trigger the automatic transfer of emergency loads. 85% of 450 VAC is 382.5 VAC, and 110% of 450 VAC is 427.5 VAC, so the emergency generator voltage must rise to a value between these two thresholds to initiate the automatic transfer.
The other options are incorrect because A) specifies a single value instead of a range, B) specifies a value higher than the allowable range, and D) specifies a range that is too broad and includes voltages outside the regulatory requirements.
Related Questions
#263 Assuming that the 3-phase power source has a phase sequence of A-B-C and that the motor is connected as shown in figure "A", if the motor has a clockwise (CW) rotation, what statement is true concerning the motors connected as shown in the other figures? Illustration EL-0156 #264 According to 46 CFR, Subchapter J (Electrical Engineering), in response to a loss of normal power or a simulated test, when will the emergency loads automatically be transferred to the emergency diesel-generator? #266 According to 46 CFR, Subchapter J (Electrical Engineering), which of the following starting aids is the ONLY method allowed to ease the starting of emergency diesel-generator engines? #267 According to 46 CFR, Subchapter J (Electrical Engineering), emergency diesel engine starting systems are required to have sufficient capacity to provide power for at least how many consecutive starts? #268 Emergency generators are required to automatically start upon a loss of normal supply voltage, according to 46 CFR, Subchapter J (Electrical Engineering). In conducting a test of the emergency generator automatic transfer of load function, if the normal system supply voltage is 480 VAC, to what value would the normal source output voltage have to rise to trigger the automatic transfer of emergency loads back to the normal power source?