FRA Locomotive Engine Systems 2

Question 1

What is the primary function of a locomotive's dynamic braking system?

Accepted Answer

Convert kinetic energy into electrical energy dissipated as heat

Answer

Dynamic braking uses traction motors as generators, converting the locomotive's kinetic energy into electrical energy that is dissipated through grid resistors as heat.

Question 2

Which cooling system component is responsible for removing heat from engine coolant in a diesel-electric locomotive?

Accepted Answer

Radiator section of the cooling tower

Answer

The radiator section of the cooling tower transfers heat from the engine coolant to ambient air via fans, maintaining safe engine operating temperatures.

Question 3

What does a locomotive's load regulator primarily control?

Accepted Answer

Engine throttle position relative to generator load

Answer

The load regulator maintains a balanced relationship between engine throttle position and generator electrical load to prevent engine lugging or overspeeding.

Question 4

In a two-stroke diesel locomotive engine, when does fuel injection occur?

Accepted Answer

Near the top of the compression stroke

Answer

Fuel is injected near top dead center of the compression stroke so combustion pressure forces the piston downward during the power event.

Question 5

What hazard is associated with high crankcase pressure in a locomotive diesel engine?

Accepted Answer

Risk of crankcase explosion or fire

Answer

Excessive crankcase pressure can force oil mist past seals, and if ignited, can cause a crankcase explosion, which is why crankcase relief valves are required.

(FRA) Federal Railroad Administration Certification Practice Test

(FRA) Federal Railroad Administration Certification Practice Test

FRA Locomotive Engine Systems 2