AEP Substation Operations Flashcards
6 cards from real AEP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 AEP Substation Operations flashcards as text
What is the primary purpose of a substation protection relay?
Answer: To detect abnormal conditions and initiate circuit breaker operation
Protection relays continuously monitor electrical parameters and trip circuit breakers when they detect faults or abnormal operating conditions.
What does lock-out/tag-out (LOTO) procedure ensure in substation work?
Answer: Hazardous energy sources are isolated before maintenance work begins
LOTO procedures ensure all energy sources are isolated and locked, preventing unexpected energization that could injure workers during maintenance.
What is the function of a load tap changer (LTC) on a substation transformer?
Answer: To adjust transformer turns ratio under load to regulate voltage
Load tap changers automatically adjust transformer winding taps while energized, maintaining output voltage within acceptable limits as load varies.
What is the minimum safe approach distance for qualified workers near energized 115 kV substation equipment?
Answer: 3.37 feet (approximately 40 inches)
OSHA and NFPA 70E specify minimum approach distances based on voltage level; for 115 kV equipment the restricted approach boundary is approximately 3.37 feet.
What is a 'dead bus' energization procedure in substation switching?
Answer: Energizing a de-energized bus section from a live source
Dead bus energization involves closing a breaker or switch to connect a de-energized bus to a live source, requiring specific verification steps beforehand.
What is the purpose of SF6 gas in gas-insulated switchgear (GIS) at substations?
Answer: To provide electrical insulation and arc quenching in sealed equipment
SF6 (sulfur hexafluoride) gas provides excellent dielectric insulation and arc extinguishing properties in GIS, allowing compact high-voltage switchgear.