IEEE 1698-2009 pdf free.IEEE Guide for the Calculation of Braking Distances for Rail Transit Vehicles.
For the purposes of this document. the following terms and definitions apply. The IEEE Siandards Dictionary: Glossary of Terms & Definitions should be referenced for terms not defined in this clausei
brake assurance: A function in the automatic train protection (ATP) system that monitors the actual achieved braking rate, and, if less than a predetennined value, applies emergency brake.
brake build-up: Thc time to achieve full commanded braking rate, beginning from the point at which a typical value of 10% of the commanded rate has been achieved.
braking rate: The deceleration of the train, resulting from the retarding effort of the braking apparatus, but excluding train resistance and grade or cunrature etTects.
curvature: The measure of the amount by which the track does not run in a straight line (i.e.. is not tangent).
dead time: The time from a point at which the instantaneous accelerating tractivc effort is zero until braking rate has reached a typical value of 10% of the commanded value.
enir point: The civil position of a train at which it enters territory wherein a more restrictive speed limit applies (i.e.. a signal boundary or transponder location).
entrs speed: The speed of the train at the entry point that is allowed by the signal system or by governing rules and procedures. This speed may include allowable speed and wayside/vehicle equipment tolerances.
equipment reaction time: The time from passage of an entry point until the carbome equipment has detected, processed. and indicated the existence of a more restrictive speed.
full service application: A service brake application of sufticient amount to obtain the maximum service brake rate obtainable.
grades: Civil changes in track elevation; the tangent of the angle formed by the algebraic value of the rise divided by the horizontal component of the run, typically expressed as a percent.
gradient: The horizontal run over which one unit of rise occurs.
jerk rate limit: The limit to the rate of change of acceleration designed into the propulsion. automatic train operation (ATO). andor braking apparatus.
maximum attainable speed: An entry speed. commonly used with trip-stops with wayside signals, which is the highest speed that a train can achieve at the entry point of the braking model while operating in accordance with the rules of the authority having jurisdiction.
maximum authorized speed: The highest speed at which a train is allowed to operate in the absence of any condition requiring a lesser speed.
operator reaction time: The time from passage of an entry point until an operator has performed a definitive action in recognition of the existence of a more restrictive speed limit.IEEE 1698 pdf download.