Open Rails Brakes - Standard Vacuum Brake Parameters
Aim - this section describes the basic standard physics parameters required to correctly define a vacuum brake in Open Rails Train Simulator.
Note: Some of the parameters used in the table below are common to the configuration of air brakes, for ease of interpretation only the vacuum braking parameters are shown in the table.
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Index
Locomotive Brake Information - General
Locomotive Brake Controller Information
Locomotive Brake Control Valve Information
Note: The default unit of measure (UoM) shown in the "Recommended Input Units" column is the UoM value that OR assumes if no UoM is included in the parameter statement.
Parameter | ENG or WAG | Description | Recommended Input Units | Suggested settings | New or Existing | Typical Examples |
---|---|---|---|---|---|---|
Wagon Brake Information | ||||||
BrakeEquipmentType ( x ) | WAG | Describes the type of brake equipment fitted to the wagon. | Text (Multiple values can be specified) | handbrake - a handbrake is fitted. vacuum_brake - a vacuum brake is fitted. | Existing | BrakeEquipmentType( "handbrake, vacuum_brake" ) |
BrakeSystemType ( x ) | WAG | Describes the type of brake system fitted to the wagon. | Text |
Vacuum_single_pipe - One pipe is used to supply and control the vacum brakes. Vacuum_twin_pipe - Two pipes are used. One controls the vacuum brakes, the other supplies the vacuum reservoir. (Currently not modelled in Open Rails) Vacuum_piped - The vehicle has no fitted brakes. It only passes on the train pipe vacuum for vacuum brakes. | Existing | BrakeSystemType ( "Vacuum_single_pipe" ) |
MaxBrakeForce ( x ) | WAG | The maximum braking force that is applied to the wagon wheel, includes the coefficient of friction for the brakeshoe. | Force - N, kN, lbf Default - Newtons | As per wagon specifications (if unknown see brake force calculator) | Existing | MaxBrakeForce ( 92.153kN ) |
MaxHandbrakeForce ( x ) | WAG | The maximum force that is applied to the wagon wheel by the handbrake. | Force - N, kN, lbf Default - Newtons | As per wagon specifications (if unknown see brake force calculator) | Existing | MaxHandbrakeForce ( 24.574kN ) |
ORTSBrakeShoeFriction ( x y ) | WAG | The coefficient of friction for the brakeshoe acting upon the wheel. | x = Factor y = Speed - kmh | As per brakeshoe specifications. Note: The corresponding MaxBrakeForce value should be calculated with a coefficient value equal to the zero kmh vale of this curve. | New | ORTSBrakeShoeFriction ( 0.0 0.49 ........ 104.6 0.288) |
MaxReleaseRate ( x ) | WAG | Maximum rate that the brake cylinder can drop pressure. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. Typically brake systems can exahust the air in the brake cylinder within seconds, so high values are not unusual. | Existing | MaxReleaseRate ( 50.0 ) |
MaxApplicationRate ( x ) | WAG | Maximum rate that the brake cylinder can drop pressure. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. Typically the brake cylinder will equalize with the auxilary reservoir within seconds, so high values are not unusual. | Existing | MaxApplicationRate ( 50.0 ) |
BrakePipeVolume ( x ) | WAG | Volume of brake pipe on wagon, including an allowance for brake hose connections between cars. | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | As per brake system specifications (the brake force calculator can assist in calculating this value). | New | BrakePipeVolume ( 0.307ft^3 ) |
ORTSDirectAdmissionValve ( x ) | WAG | Car has direct admission valves fitted | Integer | As per brake system specifications. 0 = not fitted, 1 = fitted | New | ORTSDirectAdmissionValve ( 0 ) |
ORTSAuxilaryResCapacity ( x ) | WAG | Volume of vacuum reservoir | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | As per brake system specifications. | New | ORTSAuxilaryResCapacity ( 20.0ft^3 ) |
ORTSNumberBrakeCylinders ( x ) | WAG | Number of Brake Cylinders on vehicle. | Integer | As per brake system specifications. | Existing | ORTSNumberBrakeCylinders ( 1 ) |
ORTSBrakeCylinderSize ( x ) | WAG | Diameter of brake cylinders fitted to vehicle | Distance - m, cm, mm, km, in, ft, in/2 Default - m | As per brake system specifications. | New | ORTSBrakeCylinderSize ( 18in ) |
Locomotive Brake Information - General | ||||||
VacuumBrakesMinBoilerPressureMaxVacuum ( x ) | ENG | Boiler pressure when maximum vacuum for the small ejector is produced. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | VacuumBrakesMinBoilerPressureMaxVacuum ( 110.0 ) |
ORTSBrakePipeChargingRate ( x ) | ENG | Charging rate for brake pipe, influences the pressure gradient, or how fast the air can travel to the end of the train. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. x > 1000, disables the function. This value can also be set through the option menu. | New | ORTSBrakePipeChargingRate ( 40.0InHg/s ) |
TrainPipeLeakRate ( x ) | ENG | Leakage rate for brake pipe, influences the pressure maintained in brake pipe. Leaking brake pipes can apply brakes. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. | Existing | TrainPipeLeakRate ( 0.0833InHg/s ) |
ORTSBrakePipeTimeFactor ( x ) | ENG | Influences the time for brake pressure changes to propogate through the train brake pipe along the length of the train. | Time - s, m, h Default - s | As per train brake system specifications. | New | ORTSBrakePipeTimeFactor ( 0.003 ) |
ORTSBrakeServiceTimeFactor ( x ) | ENG | Influences the time for the brake pipe pressure to drop and equate to the equalising reservoir pressure under normal operation. | Time - s, m, h Default - s | As per train brake system specifications. | New | ORTSBrakeServiceTimeFactor ( 1.009 ) |
ORTSBrakeEmergencyTimeFactor ( x ) | ENG | Influences the time for the brake pipe pressure to drop and equate to the equalising reservoir pressure under emergency operation. | Time - s, m, h Default - s | As per train brake system specifications. | New | ORTSBrakeEmergencyTimeFactor ( 0.1 ) |
ORTSBrakePipeDischargeTimeMult ( x ) | ENG | Controls propagation decrease time along train pipe as vacuum is destroyed, ie when brakes applied | Factor | As per train brake system specifications. | New | ORTSBrakePipeDischargeTimeMult ( 1.5 ) |
BrakesTrainBrakeType ( x ) | ENG | Indicates type of train brake implemented. | set to "vacuum_single_pipe_eq" or "vacuum_single_pipe" as appropriate | As per train brake system specifications. | Existing | BrakesTrainBrakeType ( "vacuum_single_pipe_eq" ) |
VacuumBrakesSmallEjectorUsageRate ( x ) | ENG | The rate that the small ejector uses steam from the boiler when it is on. Referenced to 120psi steam pressure. (Steam locomotives only). | MassRateDefaultLBpH - lb/hr Default - lb/h | As per train brake system specifications. | Existing | VacuumBrakesSmallEjectorUsageRate ( 300.0 ) |
VacuumBrakesLargeEjectorUsageRate ( x ) | ENG | The rate that the large ejector uses steam from the boiler when it is on. Referenced to 120psi steam pressure. (Steam locomotives only). | MassRateDefaultLBpH - lb/hr Default - lb/h | As per train brake system specifications. | Existing | VacuumBrakesLargeEjectorUsageRate ( 650.0 ) |
VacuumBrakesHasVacuumPump ( x ) | ENG | A vacuum pump is fitted to the locomotive. (Steam locomotives only) | Integer - 0 = No, 1 = Yes Default - No | As per train brake system specifications. | Existing | VacuumBrakesHasVacuumPump ( 0 ) |
ORTSVacuumBrakesMainResVolume ( x ) | ENG | The volume of the main vacuum brake reservoir | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | As per train brake system specifications. | New | ORTSVacuumBrakesMainResVolume ( 200.0 ) |
ORTSVacuumBrakesMainResMaxVacuum ( x ) | ENG | The maximum vacuum in the main vacuum brake reservoir. When this pressure is reached the exhauster will automatically stop running. | Pressure - psi, kPa, bar, inHg Default - psi | As per train brake system specifications. | New | ORTSVacuumBrakesMainResMaxVacuum ( 23.0InHg/s ) |
ORTSVacuumBrakesExhausterRestartVacuum ( x ) | ENG | The rate that the large ejector uses steam from the boiler when it is on. Referenced to 120psi steam pressure. (Steam locomotives only). | Pressure - psi, kPa, bar, inHg Default - psi | As per train brake system specifications. | New | ORTSVacuumBrakesExhausterRestartVacuum ( 21.0InHg/s ) |
ORTSVacuumBrakesMainResChargingRate ( x ) | ENG | The rate at which the main vacuum reservoir charges at. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default | As per train brake system specifications. | New | ORTSVacuumBrakesMainResChargingRate ( 0.2 ) |
Locomotive Brake Controller Information | ||||||
TrainBrakesController MaxSystemPressure ( x ) | ENG | Maximum pressure that the train brake pipe will operate at for the train brake system. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. | Existing | TrainBrakesController MaxSystemPressure ( 70 ) |
TrainBrakesController MaxReleaseRate ( x ) | ENG | Maximum rate the train brake controller will increase air in the train pipe, under normal brake release. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. (Only required if Equalising Reservoir fitted to brake system) | Existing | TrainBrakesController MaxReleaseRate ( 5.0 ) |
TrainBrakesController MaxApplicationRate( x ) | ENG | Maximum rate the train brake controller will release air from the train pipe, under normal brake application. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. (Only required if Equalising Reservoir fitted to brake system) | Existing | TrainBrakesController MaxApplicationRate ( 2.0 ) |
TrainBrakesController EmergencyApplicationRate( x ) | ENG | Maximum rate the train brake controller will release air from the train pipe, under emergency brake application. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. (Only required if Equalising Reservoir fitted to brake system) | Existing | TrainBrakesController EmergencyApplicationRate ( 30.0 ) |
TrainBrakesController FullServicePressureDrop ( x ) | ENG | Pressure drop resulting from a full service application of the train brake controller. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. | Existing | TrainBrakesController FullServicePressureDrop ( 25.0 ) |
Locomotive Brake Control Valve Information | ||||||
ControlName ( w x y z ) | ENG | Describes a notched control valve. | Mulitpliers | As per brake system specifications. w - minimum value of valve x - maximum value of valve y - step value of valve z - default value (setting this values determines the starting position of the brakes) | Existing | Brake_Train ( 0 1 0.01 0.25 |