railroad crossing event recorders - crash data group inc · 2020-03-02 · if train enters approach...

© 2020 – Author and Collision Publishing

Halstead – EDR Summit 1

March 9‐11, 2020 Slide 1

Railroad Crossing Event Recorders

Robert W. Halstead

President

IronWood Technologies, Inc.


Robert W. Halstead

• Railroad Accident Reconstructionist, ACTAR # 1285

• Electrical Engineer

• Former brakeman, conductor, locomotive engineer, signal design engineer and supervisor

• Past President – National Association of Railroad Safety Consultants and Investigators (NARSCI)

• Member – RailroadExperts.com

• 25 years as a Reconstructionist, 600+ cases

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(c) 2020 EDR Users Summit





Robert W. Halstead

Types of Cases Handled:

• Collisions between trains (head‐on, rear‐end, sideswipe)

• Derailments

• Crossing collisions between trains and vehicles/peds

• Collisions with peds at other than crossings

• Platform gap injuries

• Electrocution

• Railroad employee injuries (FELA)

• Accident reenactments

• Crossing design


Topics

• Basics of Crossing Train Detection and Operation

• Basic and Advanced Crossing Event Recorders

• Synchronization of crossing event data with other sources of train data, depiction on single chart

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Crossing Types (by Usage)

Private Crossing

• 80,073 in 2015

• Owned and maintained by private landowner

Public Crossing

• 129,582 in 2015

• “A location where a public highway, road or street, including associated sidewalks or pathways, crosses one or more railroad tracks at grade. In the event a public authority maintains the roadway on both sides of the crossing, the crossing is considered a public crossing for purposes of this part.” (49 CFR § 222.9)


Crossing Types (by Warning Type)

Passive Warning Devices

• Do not change their visual appearance upon the approach of a train

• Crossbucks – may or may not be supplemented by Yield or Stop sign

Active Warning Devices

• Change their physical appearance upon the approach of a train

• May be flashers only – or be supplemented by gates and/or cantilevers

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Crossing Control Cabinets ‐ Types

• Crossing Instrument Case (i.e. – “High Double”)


Crossing Control Cabinets ‐ Types

• Crossing Instrument Location (“CIL”) or “Bungalow”

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Grade Crossing Warning System

Normal Standby

Grade Crossing Predictor (GCP) Unit



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EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit

Shunt ShuntXmtr Rcvr

Predictor


Grade Crossing Warning SystemTrack Wire Connections to Rail

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Track Circuit Termination Shunt


Basic Motion Sensor or CWT Operation

EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Motion Sensor

Vol

tage

Time

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EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Predictor

Vol

tage

Time



EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Predictor

Vol

tage


Time

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EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Predictor

Vol

tage

Time


EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Predictor

Vol

tage

Time


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EastwardApproach

Circuit

East

WestwardApproach

Circuit

IslandCircuit


Predictor

Vol

tage

Time



3,476’

Shunt

IslandCircuit

30 sec @ 79 MPH

60 sec @ 40 MPH

120 sec @ 20 MPH


Crossing Approach Length Based on Maximum Authorized Speed for Trains

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If train enters approach and then stops, crossing initially activates as usual, and then after the train has been stopped for

10 seconds, the system recovers and deactivates the active warning devices

If train then resumes movement toward the crossing, the system reactivates the active warning devices.

If train then resumes movement away from the crossing, the system does not reactivate the active warning devices.




Two basic types of crossing malfunctions:

• False ActivationWarning devices active with no trains approaching the crossing

• Failure to ActivateWarning devices either fail to activate for an approaching train or provide less than the minimum required warning time

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Minimum Required Warning Time:

20 seconds (or as designed)

from the instant at which the flashers begin to flash until the leading edge of the train occupies the highway (49 CFR § 234.225)

In addition, the gates (if any) must be fully horizontal a minimum of

5 seconds

before the leading edge of the train occupies the highway (49 CFR § 234.223)



Basic MS or CWT Unit Data Download

Warning Time

Detect Speed

Average Speed

Island Speed

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Basic MS or CWT Unit Data Download


Harmon HCA‐1

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Light‐Out Detectors


Recordable Parameters Include:

• Train Speeds

• Warning Time

• Lights Flashing

• Gate Movement & Position

• Traffic Signal Preemption Active

• Commercial Power On/Off

• Battery Voltage

• Lighting Buss Voltages

• Time Island Circuit Occupied

• Stopped Vehicle Detection

• Record Faults, report to external computer/personnel for repair

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railroad crossing event recorders - crash data group inc · 2020-03-02 · if train enters approach...

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