What is the function of a Neutral Grounding Resistor (NGR) in marine HV electrical systems?
Direct Answer
Option B: Limit earth fault current to a safe value (e.g. 10A - 20A), preventing core damage during single phase-to-ground faults
Neutral Grounding Resistors (NGR) are essential in high-resistance grounded systems to limit earth fault current. By restricting current to a low value, typically 10A to 20A, the NGR prevents severe arcing and thermal damage to the generator stator core, ensuring the system remains operational during a single-phase fault.
All Options
Detailed Explanation & Context
Neutral Grounding Resistors (NGR) are essential in high-resistance grounded systems to limit earth fault current. By restricting current to a low value, typically 10A to 20A, the NGR prevents severe arcing and thermal damage to the generator stator core, ensuring the system remains operational during a single-phase fault.
Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • High Voltage Safety Officer & Switchgear Operations (HV).
Practice Full HV Set 1
Test yourself with 30 interactive questions, live timer, and instant score.