While underway onboard a DC diesel-electric...

Question 1 / 270705eccefa4bacbc34ba4d485d2

Question 1 of 270705eccefa4bacbc34ba4d485d2

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?

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Question 1 of 27070

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?

🔍 Key Concepts

• DC motor brush sparking causes such as overload, poor commutation, or field/armature issues • Effect of changing generator voltage or speed on a DC propulsion motor • What happens to motor current and load when you change the motor field current

💭 Think About

• Think about which single adjustment you can make immediately and locally that most directly affects brush sparking on a DC motor • Consider how each option would change motor current, commutation quality, and load on the brushes • Ask yourself which action might actually make sparking worse rather than better, even if it sounds helpful at first

✅ Before You Answer

• For each choice, predict whether armature current will increase or decrease, and how that affects sparking • Check which action affects the motor itself versus affecting the generator or ship operations more generally • Verify which adjustment would most likely improve commutation at the brushes rather than simply reducing total power output

Question 1 of 27070

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?

decrease the main generator voltage

decrease the speed of the main generator

notify the bridge that you will need to slow down to reduce the electrical load

decrease the motor field current

Question 1 / 270705eccefa4bacbc34ba4d485d2

Question 1 of 270705eccefa4bacbc34ba4d485d2

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?

Back

Question 1 of 27070

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?