Question 59 OSE02 - Assistant Engineer - OSV

The Correct Answer is A. **Explanation for Option A (Correct Answer):** The Woodward SG (Standard Governor) type is a widely used mechanical-hydraulic speed-droop governor primarily designed for prime movers where isochronous (constant speed regardless of load) operation is not critical, or where the engine is driving an AC generator and droop is required for load sharing. However, even the basic SG model typically includes several essential control features in addition to the main speed setting control (which adjusts the spring tension for the desired governed speed): 1. **Minimum Governed Speed Setting (Engine Idle Speed):** This feature ensures that the engine can maintain a stable, low RPM when disengaged or lightly loaded (e.g., while waiting for the winch operation to start). It acts as the lower limit of the governor's speed range. 2. **Maximum Governed Speed Setting (Engine Speed Limit):** This setting mechanically limits the maximum speed the governor will allow the engine to reach, regardless of how far the operator moves the speed lever. This is a crucial safety and longevity feature to prevent engine over-speeding. For applications like a winch engine on a tug, having easily adjustable idle speed and a hard maximum speed limit are fundamental requirements of the control package, and these adjustments are standard mechanical stops built into the SG governor's control linkage. **Explanation for Incorrect Options:** * **B) Engine idle speed (minimum governed speed), engine load limit (maximum fuel delivery):** While the SG governor controls the fuel rack position (which dictates fuel delivery), the *maximum fuel delivery (load limit)* setting is typically a feature of the **fuel injection pump** itself (a mechanical stop known as the "smoke stop" or rack stop), not an adjustment directly built into the primary mechanics of the standard SG governor head. The governor controls speed, and speed indirectly limits fuel, but the mechanical load limit is usually separate. * **C) Engine load limit (maximum fuel delivery), engine speed limit (maximum governed speed):** As explained above, the maximum fuel delivery (load limit) is generally a component of the fuel pump assembly, not the governor head itself. The maximum speed limit is correct, but the load limit makes this option incorrect. * **D) Engine speed droop (load sharing adjustment), governor compensation (stability adjustment):** Both speed droop and compensation are fundamental *characteristics* or *internal adjustments* of the SG governor, crucial for its operation (droop is the defining characteristic of the SG). However, they are internal calibration settings used to tune the governor's performance and stability, not the "group of settings" that the operator uses to define the operational *range* of the engine (idle and max speed limits). Option A describes the operational boundary settings provided to the user/operator, which are distinctly separate from the variable speed control.