Switching Operations Flashcards
7 cards from real SOPD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Switching Operations flashcards as text
A 'bus tie breaker' is operated normally closed. During maintenance switching, it is opened to create:
Answer: A split-bus configuration with each bus served by its own source
Opening the bus tie breaker separates the double-bus arrangement into two independent radial buses, each fed by its own source.
During a high-impedance fault on a distribution feeder, the protective relay may NOT operate automatically. The operator's appropriate response is to:
Answer: Dispatch field crews to patrol the line and report findings before switching
High-impedance faults (e.g., downed conductors on asphalt) often do not trip overcurrent relays, requiring field patrol to locate the hazard before switching.
The purpose of a 'switching hold' placed by the Energy Control Center is to:
Answer: Prevent any switching on a specific device or circuit pending system conditions or study results
A switching hold prevents any operation on the specified device until the ECC removes the hold, typically due to system stability, study, or safety concerns.
Switching capacitor banks on a transmission system can produce transient overvoltages. The best mitigation during scheduled switching is to:
Answer: Use pre-insertion resistors or controlled closing (point-on-wave) switching
Pre-insertion resistors or point-on-wave controlled closing reduce inrush transients by limiting the rate of voltage change during energization.
After completing all steps of a switching order, the operator must:
Answer: File the order and update the system one-line diagram or EMS model to reflect the new configuration
Updating the system model or one-line diagram ensures all operators have an accurate picture of the current network configuration.
A 'cold load pickup' condition following a prolonged outage is characterized by:
Answer: High inrush current as thermostatically controlled loads restart simultaneously
After a long outage, thermostatic loads (HVAC, water heaters) all call for power simultaneously, causing inrush current several times normal load.
Which action is required before racking a drawout circuit breaker from the 'test' position to the 'connected' position in a metal-clad switchgear cubicle?
Answer: Verify the breaker is in the OPEN position
The breaker must be open before racking into the connected position to prevent closing onto a live bus unexpectedly.