WMATA Rail Systems 2 — Questions and Answers
Question 1: What does a red signal aspect on a Metrorail wayside or cab signal indicate to a train operator?
- Stop and do not proceed without authorization (Correct answer)
- Proceed at full speed
- Reduce speed to 35 mph
- Approach the next station
Correct answer: Stop and do not proceed without authorization
A red signal requires the operator to stop and obtain authorization before proceeding.
Question 2: On WMATA Metrorail, the third rail supplies traction power at approximately what voltage?
- 750 volts DC (Correct answer)
- 120 volts AC
- 25,000 volts AC
- 12 volts DC
Correct answer: 750 volts DC
Metrorail's third rail carries roughly 750 volts DC to power the trains.
Question 3: Before fouling the track or contacting the third rail area, a worker must confirm that power has been:
- Deenergized and verified with a confirmation (Correct answer)
- Reduced to half voltage
- Switched to backup
- Left on for testing
Correct answer: Deenergized and verified with a confirmation
Power must be confirmed deenergized before anyone works near the third rail.
Question 4: What is the primary purpose of an interlocking in a rail system?
- To prevent conflicting train movements through switches and signals (Correct answer)
- To charge train batteries
- To clean the rails
- To announce stations
Correct answer: To prevent conflicting train movements through switches and signals
Interlockings control switches and signals so conflicting routes cannot be set simultaneously.
Question 5: If a train operator loses radio contact with the Rail Operations Control Center, the correct action is to:
- Stop the train and attempt to reestablish communication (Correct answer)
- Continue at full speed
- Ignore it until the next station
- Reverse direction immediately
Correct answer: Stop the train and attempt to reestablish communication
Loss of communication requires stopping and reestablishing contact before proceeding.
Question 6: Automatic Train Control (ATC) on Metrorail is mainly designed to:
- Maintain safe spacing and enforce speed limits between trains (Correct answer)
- Sell fare cards
- Light the stations
- Open platform doors
Correct answer: Maintain safe spacing and enforce speed limits between trains
ATC enforces safe separation and speed limits to prevent collisions.
Question 7: A 'gauge' in railroad terms refers to the distance between:
- The inner faces of the two running rails (Correct answer)
- Two stations
- Signal posts
- Platform edges
Correct answer: The inner faces of the two running rails
Track gauge is the measured distance between the inner faces of the running rails.
WMATA Rail Systems 2
What does a red signal aspect on a Metrorail wayside or cab signal indicate to a train operator?