Air Brakes and Train Handling Rules - Alaska Railroad

GlossaryLocomotive Cab Unit (LCU)A telemetry transmitter/receiver that provides the locomotiveengineer with the displays and controls needed to monitor andoperate the associated EOT device.L/V RatioThe ratio of lateral force (a wheel trying to climb the rail) to thevertical force (weight of a car or locomotive and its load).Excessive L/V can contribute to rail turnover, wheel climb, andderailments.Main ReservoirA reservoir on a locomotive that stores, cools, and dries thesupply of compressed air.Minimum ReductionA 5 to 7 psi service brake pipe reduction. It takes advantage of“quick service” and minimizes in-train forces caused by theserial action of a brake application.MU-2A ValveA device used to cut the independent brake valve in or out.Multiple Unit (MU) ConnectionsThe hoses and cocks at both ends of locomotives that connect airbrake equipment in a locomotive consist, allowing operationfrom a single control. MU connections include:Actuating (ACT): When charged with main reservoir air, causesa release of an automatic brake application on locomotives.Independent Application and Release (IAR): Controls independentbrakes on locomotives from a single control.Main Reservoir (MR): Equalizes the main reservoir pressurebetween locomotives.Brake Pipe: The pipe, angle cocks, hose, and hose couplingsthat distribute compressed air throughout the automatic brakesystem.G-10 ARRC Air Brakes and Train Handling Manual June 1, 1996