Question 458Motor Plants - Assistant Engineer

The correct answer is A) Device 17A needs to be replaced, repaired, or reset to the setpoint coinciding with the RPM value for the low end of the critical speed range. This is the correct answer because if the propulsion engine fails to function at speeds lower than the low end of the critical speed range, it indicates an issue with the speed control circuit, specifically with device 17A. Device 17A is likely malfunctioning or not set to the proper RPM value for the low end of the critical speed range, which is preventing the engine from operating at those lower speeds. Resetting or repairing 17A should correct the issue and restore the engine's functionality within the critical speed range. The other options are incorrect because they either suggest adjusting the wrong components (options B and D) or do not address the root cause of the problem (option C).