Open Rails Brakes - Standard Parameters
Aim - this section describes the standard physics parameters required to correctly define different brake types in Open Rails Train Simulator.
If you wish to provide any feedback on this page, please use the contact page. It would be great to have some feedback as this helps to ensure the accuracy of the information and models.
Index
Locomotive Brake Information - Compressor or Ejector, Reservoir and 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.
The ENG or WAG column also indicates which brake system that they can be used with, and has the following legend, S = Steam, A = Air, V = Vacuum.
| Parameter | ENG or WAG | Description | Recommended Input Units | Suggested settings | New or Existing | Typical Examples |
|---|---|---|---|---|---|---|
| Wagon Brake Information | ||||||
| NumberOfHandbrake LeverSteps ( x ) | WAG A, V, M | Not currently defined in OR code. | Existing | |||
| BrakeEquipmentType ( x ) | WAG A, V, M | Describes the type of brake equipment fitted to the wagon. | Text (Multiple values can be specified) | handbrake - a handbrake is fitted. manual_brake - a manual brake fitted. retainer_3_position - a 3 position retaining valve is fitted. retainer_4_position - a 4 position retaining valve is fitted. This meant for freight wagons only. Only a either a 3 or 4 position retainer is meant to be selected. graduated_release_triple_valve - a triple valve that permits partial releasing of the brakes. auxiliary_reservoir - air tank used for normal service brake applications. This is required for all brake systems. emergency_brake_reservoir - air tank used for emergency applications. This is optional. distributor - electronic or computer controller on the vehicle that can be set to independently control any parameter of the braking system. | Existing | BrakeEquipmentType( "Triple_valve, Auxilary_reservoir" ) |
| BrakeSystemType ( x ) | WAG A, V, M | Describes the type of brake system fitted to the wagon. | Text | Air_single_pipe - One pipe controls and supplies the air brakes. Manual_Braking - The car uses a manual braking system. Air_single_pipe - One pipes is used to control the brakes, and to charge the reserviors. Air_twin_pipe - Two pipes are used. One to control the brakes, the other to charge the reserviors. Vacuum_single_pipe - One pipe is used to supply and control the vacuum brakes. Straight_vacuum_single_pipe - One pipe is used to supply and control the vacuum brakes. This is a straight vacuum brake as opposed to the more modern automatic vacuum brake. Vacuum_twin_pipe - Two pipes are used. One controls the vacuum brakes, the other supply the vacuum reservior. ECP - The brakes are controlled by a computer or complex electronic control system. EP - The brakes are a combination of standard air brakes and electrical control signals. SME - The brakes are a combination of a straight air brakes and electrical control signals. Air_piped - The vehcile has no powered brakes. It only passes on the train pipe pressure for air brakes. Vacuum_piped - The vehicle has no powered brakes. It only passes on the train pipe pressure for vacuum brakes. | Existing | BrakeSystemType ( "Air_single_pipe" ) |
| MaxBrakeForce ( x ) | WAG A, V, M | 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. NB: Ideally the brake shoe force should be used (see next parameter). | Existing | MaxBrakeForce ( 92.153kN ) |
| ORTSMaxBrakeShoeForce ( x ) | WAG A, V, M | The maximum braking force that is applied to the brake shoe on the wagon wheel. | Force - N, kN, lbf Default - Newtons | As per wagon specifications (if unknown see brake force calculator) | New | ORTSMaxBrakeShoeForce ( 122.153kN ) |
| MaxHandbrakeForce ( x ) | WAG A, V, M | 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 A, V, M | The coefficient of friction for the brakeshoe acting upon the wheel. | x = speed in kph y = brakeshoe friction | As per brakeshoe specifications. | New | ORTSBrakeShoeFriction ( 0.0 0.49 ........ 104.6 0.288) |
| ORTSNumberCarBrakeShoes ( x ) | WAG A, V, M | Number of brake shoes fitted on car. | Multiplier | As per brake system specifications. | New | ORTSNumberCarBrakeShoes ( 16 ) |
| ORTSBrakeShoeType ( x ) | WAG A, V, M | Describes the brakehsoe type fitted to the car. | Cast_Iron_P6 - P6 Cast iron default 2D curve, Cast_Iron_P10 - P10 Cast iron default 2D curve, High_Friction_Composite - high friction composite default 2D curve, Disc_Pads - Disc pads default 2D curve User_Defined - User defined 1D curve (uses brake shoe friction curve above) | As per brake system specifications. | New | ORTSBrakeShoeType ( CastIron_P6 ) |
| EmergencyResVolumeMultiplier ( x ) | WAG A | Ratio of emergency reservoir compare to auxiliary reservoir. (R = EmerRes / AuxRes) | Multiplier | As per brake system specifications. | Existing | EmergencyRes VolumeMultiplier ( 1.0 ) |
| TripleValveRatio ( x ) | WAG A | Ratio of the brake cylinder and the auxilary reservoir volumes. | Multiplier | As per brake system specifications. Typically on most braking systems this is 2.5. | Existing | TripleValveRatio ( 2.5 ) |
| MaxReleaseRate ( x ) | WAG A, V, M | 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 A, V, M | 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 ) |
| MaxAuxilaryChargingRate ( x ) | WAG A | Maximum rate that the auxiliary resevoir can be refilled at. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. Typically the auxiliary reservoir will equalize with the air brake pipe or main reservoir pipe in less than a minute. | Existing | MaxAuxilaryChargingRate ( 20.0 ) |
| EmergencyResChargingRate ( x ) | WAG A | Maximum rate that the emergency resevoir can be refilled at. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. Typically the emergency reservoir will charge more slowly than the auxiliary reservoir. | Existing | EmergencyResChargingRate ( 20.0 ) |
| EmergencyResCapacity ( x ) | WAG A | Volume of emergency reservoir. | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | As per brake system specifications. (Note this parameter is required, as the auxilairy reservoir volume is calculated form it. To calculate the size of the auxilairy reservoir, firts calculate the size of the brake cylinder first) | Existing | EmergencyResCapacity ( 1.792ft^3 ) |
| BrakeCylinderPressureFor MaxBrakeBrakeForce ( x ) | WAG A | Pressure needed in the brake cylinder for maximum braking force. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | BrakeCylinderPressureFor MaxBrakeBrakeForce ( 50.0 ) |
| BrakePipeVolume ( x ) | WAG A, V | 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 V | Car has direct admission valves fitted | Integer | As per brake system specifications. 0 = not fitted, 1 = fitted | New | ORTSDirectAdmissionValve ( 0 ) |
| ORTSAuxilaryResCapacity ( x ) | WAG V | 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 V | Number of Brake Cylinders on vehicle. | Integer | As per brake system specifications. | Existing | ORTSNumberBrakeCylinders ( 1 ) |
| ORTSBrakeCylinderSize ( x ) | WAG V | 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 ) |
| ORTSWheelBrake SlideProtection ( x ) | WAG A | Car has wheel slide protection fitted. | Integer | As per brake system specifications. 0 = not fitted, 1 = fitted | New | ORTSWheelBrake SlideProtection ( 0 ) |
| ORTSWheelBrakesSlide ProtectionLimitDisable ( x ) | WAG A | Disable brake pipe limit on wheel slide protection system. | Integer | As per brake system specifications. 0 = not fitted, 1 = fitted | New | ORTSWheelBrakesSlide ProtectionLimitDisable ( 0 ) |
| Locomotive Brake Information - Compressor or Ejector, Reservoir and General | ||||||
| AirBrakesAir CompressorWattage ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| AirBrakesMainMinRes AirPressure ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| AirBrakesAirUsedPerPoundsOf BrakePipePressure ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| AirBrakesHasLowPressureTest ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| AirBrakesAirCompressor PowerRating ( x ) | ENG A | This appears to be used to enter the Compressor Charging Rate, but this is better done by using ORTSMainResChargingRate. | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | Legacy parameter. | Existing | Recomend not using, and use ORTSMainResChargingRate instead. |
| ORTSLocomotive DriveWheelOnlyBraking ( x ) | ENG A | Determines whether both drive and non-drive wheels are braked. | Integer | As per locomotive specifications, where x =1 (Drive Wheels only) x = 0 (Braking on all locomotive wheels). Applys to steam locomotives only. | New | ORTSLocomotive DriveWheelOnlyBraking ( 1 ) |
| AirBrakesMainMaxAir Pressure ( x ) | ENG A | Maximum air pressure in the main air brake reservoir. When this pressure is reached the compressor will automatically stop running. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | AirBrakesMainMaxAir Pressure( 105.0 ) |
| AirBrakeMaxMainRes PipePressure ( x ) | ENG A | The maximum pressure that the main reservoir pipe can reach. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. (only to be used with twin pipe systems) | Existing | AirBrakeMaxMainRes PipePressure( 95.0 ) |
| AirBrakesCompressor RestartPressure ( x ) | ENG A | Pressure below which the compressor will start to recharge the main reservoir. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | AirBrakesCompressor RestartPressure( 90.0 ) |
| AirBrakesMainResVolume ( x ) | ENG A | Pressure below which the compressor will start to recharge the main reservoir. | VolumeDefaultFT3 - ft^3, in^3, m^3, l, g-uk, g-us Default - ft^3 | As per brake system specifications. | Existing | AirBrakesMainResVolume ( 20.490ft^3 ) |
| ORTSMainResChargingRate ( x ) | ENG A | Recharging rate for main reservoir, depends upon the capacity of the air compressor. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. (if unknown see brake force calculator) | New | ORTSMainResChargingRate ( 0.237 ) |
| ORTSBrakePipeChargingRate ( x ) | ENG A, V | 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 ( 40.0 ) |
| TrainPipeLeakRate ( x ) | ENG A, V | 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 ( 0.0833 ) |
| ORTSBrakePipeTimeFactor ( x ) | ENG A, V | 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 A, V | 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 ) |
| ORTSBrakeEmergency TimeFactor ( x ) | ENG A, V | 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 | ORTSBrakeEmergency TimeFactor ( 0.1 ) |
| ORTSBrakePipe DischargeTimeMult ( x ) | ENG V | Controls propagation decrease time along train pipe as vacuum is destroyed, ie when brakes applied | Factor | As per train brake system specifications. | New | ORTSBrakePipe DischargeTimeMult ( 1.5 ) |
| BrakesTrainBrakeType ( x ) | ENG V | 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" ) |
| VacuumBrakesSmall EjectorUsageRate ( x ) | ENG V | 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 | VacuumBrakesSmall EjectorUsageRate ( 300.0 ) |
| VacuumBrakesLarge EjectorUsageRate ( x ) | ENG V | 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 | VacuumBrakesLarge EjectorUsageRate ( 650.0 ) |
| VacuumBrakesHasVacuumPump ( x ) | ENG V | 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 ) |
| ORTSVacuumBrakes MainResVolume ( x ) | ENG V | 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 | ORTSVacuumBrakes MainResVolume ( 200.0 ) |
| ORTSVacuumBrakesMainRes MaxVacuum ( x ) | ENG V | 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 | ORTSVacuumBrakesMainRes MaxVacuum ( 23.0InHg/s ) |
| ORTSVacuumBrakesExhauster RestartVacuum ( x ) | ENG V | 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 | ORTSVacuumBrakesExhauster RestartVacuum ( 21.0InHg/s ) |
| ORTSVacuumBrakesMainRes ChargingRate ( x ) | ENG V | 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 | ORTSVacuumBrakesMainRes ChargingRate ( 0.2In/Hg ) |
| VacuumBrakesVacuum PumpResistance ( x ) | ENG V | The resistance that the vacuum pump puts on the locomotive pulling power. | Force - N, kN, lbf Default - Newtons | As per train brake system specifications. | New | VacuumBrakesVacuum PumpResistance ( 1000N ) |
| Locomotive Brake Controller Information | ||||||
| EngineBrakesController HasProportionalBrake ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| EngineBrakes ProportionalBrakeLag ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| EngineBrakesController MinSystemPressure ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| EngineBrakesController EmergencyBrakeTimePenalty ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| EngineBrakesController DirectControlExponent ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| TrainBrakesController MinSystemPressure ( x ) | ENG A | Not currently defined in OR code. | Existing | |||
| TrainBrakesController MaxSystemPressure ( x ) | ENG A, V | 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 A, V | 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. | Existing | TrainBrakesController MaxReleaseRate ( 5.0 ) |
| TrainBrakesController MaxQuickReleaseRate ( x ) | ENG A | Maximum rate the train brake controller will increase air in the train pipe, under quick brake release. | PressureRateDefaultPSIpS - psi/s, kPa/s, bar/s, inHg/s Default - psi/s | As per brake system specifications. | Existing | TrainBrakesController MaxQuickReleaseRate ( 20.0 ) |
| TrainBrakesController MaxApplicationRate( x ) | ENG A, V | 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. | Existing | TrainBrakesController MaxApplicationRate ( 2.0 ) |
| TrainBrakesController EmergencyApplicationRate( x ) | ENG A, V | 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. | Existing | TrainBrakesController EmergencyApplicationRate ( 30.0 ) |
| TrainBrakesController FullServicePressureDrop ( x ) | ENG A, V | Pressure drop resulting from a full service application of the train brake controller. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | TrainBrakesController FullServicePressureDrop ( 25.0 ) |
| TrainBrakesController MinPressureReduction ( x ) | ENG A | Pressure that will be dropped by a minimum reduction setting on the train brake controller. | Pressure - psi, kPa, bar, inHg Default - psi | As per brake system specifications. | Existing | TrainBrakesController MinPressureReduction ( 7.0 ) |
| Locomotive Brake Control Valve Information | ||||||
| ControlName ( w x y z ) | ENG A, V, M | 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 |
| ORTSSmallEjector ( w x y z ) | ENG A, V, M | Describes a notched control valve which operates the small steam ejector. | 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) | New | ORTSSmallEjector( 0 1 0.1 0.55 ) |