Question 25 1AE01 - First Assistant Engineer

The Correct Answer is B **Explanation for Option B (Correct Answer):** Option B states that failure to start the hydraulic pump drive motor could be the result of an electrical interlock associated with the hydraulic pump stroke control being in a position *other than* neutral. This is a standard safety feature in electro-hydraulic machinery, especially anchor windlasses. The hydraulic pump motor is typically high-horsepower and drives a variable-displacement pump. If the pump's displacement (stroke) is not at zero (neutral position) when the motor starts, the motor would immediately attempt to drive the pump under a significant load (due to high system pressure or the force required to move the fluid at full stroke). This excessive starting load could cause high current draw, trip circuit breakers, or damage the motor or the coupling. Therefore, an electrical interlock is implemented to ensure the pump stroke is confirmed to be zero (neutral) before the drive motor is permitted to start, protecting the system from overload. If the stroke control is *not* in neutral, the interlock prevents the motor from starting. **Explanation for Incorrect Options:** **A) Failure to start could be the result of an electrical interlock associated with handwheel operated wildcat band brakes being set.** This is incorrect. While the wildcat brakes being set (applied) might prevent operation of the windlass (i.e., prevent the shaft from turning), it is generally not an interlock that prevents the *electric motor from starting*. The motor must be running to build hydraulic pressure before any operation can occur. Preventing the motor from starting based on the brake position is typically unnecessary, as the pump can run at zero stroke without moving the machinery. **C) Failure to start could be the result of an electrical interlock associated with the wildcat clutches being disengaged.** This is incorrect. The clutches being disengaged means the wildcat (chain gypsy) is disconnected from the main drive shaft. Disengaged clutches mean less load or no operational requirement on the windlass machinery. An interlock would typically prevent operation (turning the wildcat) if the clutches were engaged *and* the brakes were set, but it would not typically prevent the motor from starting. Running the motor with disengaged clutches and zero pump stroke is the normal standby condition. **D) Failure to start could be the result of an electrical interlock associated with the hydraulic pump stroke control being in the neutral position.** This is the opposite of the required safety condition. Being in the neutral (zero stroke) position is the *permissive* condition that allows the motor to start, as it minimizes the starting load on the motor. An interlock would prevent starting if the control was *not* in neutral (as correctly stated in B), but it would never prevent starting simply because it *is* in neutral.