Question 264Electricity & Electronics - 1st Asst/Chief

70% to pass

While underway onboard a DC diesel-electric drive ship, you notice excessive sparking of the brushes on the main propulsion motor. What should be your FIRST action?

Adecrease the speed of the main generator
Bdecrease the main generator voltage
Cnotify the bridge that you will need to slow down to reduce the electrical load
Ddecrease the motor field current
AI Explanation

The correct answer is C) notify the bridge that you will need to slow down to reduce the electrical load. Excessive sparking of the brushes on the main propulsion motor indicates an issue with the electrical system, likely caused by an overload. The first action should be to notify the bridge so they can reduce the ship's speed, which will in turn reduce the electrical load on the system. This will help mitigate the sparking and prevent potential damage to the motor. The other options are incorrect because decreasing the speed of the main generator (A) or the main generator voltage (B) may not directly address the issue with the propulsion motor. Decreasing the motor field current (D) could potentially worsen the problem by further reducing the motor's performance.

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