Question 244Electricity & Electronics - Assistant Engineer

The correct answer is B) not to exceed 15% above rated speed. According to 46 CFR Subchapter J, each diesel engine driven generator prime mover must have an overspeed device that is independent of the normal operating governor. The regulations specify that the overspeed trip point setting should not exceed 15% above the rated speed of the engine. This is to ensure that the overspeed protection is activated at a safe limit to prevent potential damage or failure of the engine and generator system. The other options are incorrect because they do not align with the regulatory requirement. Setting the overspeed trip point higher than 15% above rated speed would not provide adequate protection against engine overspeed events.