Railway
Infrastructure and
Train Control
presented to - CE 433
University of Kentucky
Raymond J Rumsey, PE
Assistant VP C&S
Norfolk Southern Railway
October 24, 2012
OUTLINE
 Purpose
of signal systems
 Blocks
 Track
Circuits-insulated rail joints, relays,
shunt
 Fixed Signals
 Automatic Block signals
OUTLINE
 Interlocking
 Control
Points
 Switches, crossover, diamond and trackwork
 Detectors
 Next generation train control – PTC
SIGNALS AND TRAIN CONTROL
SAFELY MAXIMIZE TRACK UTILIZATION
SIGNAL SYSTEMS
Locate Trains
Control & Verify
Switch Position
Control & Verify
Signal Position
Inform Motorists Inform Other
Trains
Highway
Crossing
Warning
Lock Switches
and Signals
Block Signals
Inform Trains
Interlocking
SIGNALS
The signal system is set up in
blocks.
 Limits defined by insulated joints
 Based on the track circuit

Rails
 Battery
 Relay

INSULATED RAIL JOINTS
Insulated joints are the means by which a track circuit
is limited or defined. The insulated joint prevents
current from flowing between the adjacent ends of
two adjoining rails.
There are different kinds of insulated
joints, made out of different materials
but the concept is the same. The joint
bars are metal. They are insulated from
the rail wherever there is contact by
pieces of insulation.
The pieces of insulation are
head and base pieces.
RELAYS
SHUNT
A device which allows an electrical
current to pass around another point
in that circuit.
A shunt is also a wire consisting of
two metal "C" clamps which
complete an electrical circuit
between rails, simulating track
occupancy during banner checks.
FIXED SIGNAL
A signal of fixed
location indicating a
condition affecting
the movement of a
train or engine.
SIGNALS
Position Light Signal
Color Light Signal
Color Position Light Signal
SIGNALS – POWER CONSIDERATIONS
SIGNAL ADDITIONS
Number Plate
Letter Plate
Flashing Light
Semaphore Arm
AUTOMATIC BLOCK
The block signal automatically indicates track condition and
block occupancy.
CAB SIGNALS
A signal located in
the operating
compartment of the
controlling
locomotive
indicating track
occupancy or
condition
INTERLOCKING
An arrangement of signals and signal appliances so interconnected that their
movements must succeed each other in proper sequence. They are found at a
crossing of two railroads, a drawbridge, a junction, or entering or leaving a
terminal or yard.
INTERLOCKING
An arrangement of signals and signal appliances so interconnected that their
movements must succeed each other in proper sequence. They are found at a
crossing of two railroads, a drawbridge, a junction, or entering or leaving a
terminal or yard.
CONTROLLED POINT
A station designated in
the timetable where
signals are controlled
from the control station
CONTROLLED POINT
A control point can
define the limits of a
junction of separate
lines.
SWITCHES
Switch and turnout are the terms used to describe the
arrangement of rails that allows junctions to be made in
the track.

Turnout is commonly used by track engineers, while switch is
more common among signal employees.
CROSSOVER
Two turnouts in
which the track
between the frogs is
arranged to form a
continuous passage
between two nearby
and generally parallel
tracks.
DIAMOND
An intersection of two
sections of track. The
term refers to the
diamond shape the four
connected frogs make
when one track crosses
another
FROG
Term for the track
component of a
crossover or a
diamond which allows
the wheel flanges ways
to cross diverging
tracks.
HAND-THROW SWITCH
DUAL CONTROLLED SWITCH
A power operated switch that is also equipped for
hand-throw operation.
SWITCH GAP
The term used to
describe the space
between the switch
point and the rail
that allows the
wheels of the
rolling equipment
to travel the route
for which the
switch is lined.
SPRING SWITCH
A switch equipped with a spring
mechanism arranged to restore
the points to normal position
after having been trailed
through.
TRAILING POINT MOVE
The movement of a train over the
points of a switch which face the
direction in which the train is moving.
ELECTRIC SWITCH LOCK
Their function is to keep unauthorized people from
tampering with equipment and to keep a train on a
siding or spur from pulling out on the mainline in front
of an oncoming train.
ELECTRIC SWITCH LOCK
When a train
wants to come
out of the siding,
the trainman
activates the ESL.
Once the ESL is activated, the protecting signals for the
siding turn red. At the same time, the timing device
electronically associated with the ESL is activated. A set
amount of time has to elapse before the trainman can
complete the operation to unlock switch points.
UNUSUAL OCCURRENCE DETECTORS
These devices can be connected to or a part of the signal
system. Their purpose is to detect unusual occurrences
on the rail. They include:

Dragging Equipment / Hot Box / Hot Wheel Detector

High water detectors

Slide fences

Earthquake detectors

Remote control locomotive zone limiting devices

Slump / Ballast Movement / Slide / Avalanche Detectors

High/Wide Load

Wheel Impact Load Detector

Scour Detectors
HOT BOX DETECTOR
A heat sensitive device
installed along railroad
main line track at
strategic locations for
measuring the relative
temperatures of passing
journal bearings
SLIDE FENCE
Part of a railway signaling system,
a slide fence is a fence whose
purpose is to prevent trains from
being derailed by rock slides in
mountainous areas where rock
slides may occur without
warning.
DERAIL
A track device designed to
guide equipment off the rails at a
selected location as a means of
protection
FIRST CAME THIS

Collision of Metrolink Train 111 with Union Pacific Train LOF65–12 Chatsworth, California, September 12, 2008

Roadway Workers Struck by Amtrak Acela Train 2154, Providence, Rhode Island, March 13, 2008

Rail Grinder Derailment on Union Pacific Railroad, Baxter, California, November 9, 2006

Derailment of CSX Transportation (CSX) freight train Q380-09 in Painesville, Ohio, October 10, 2007

Collision of Amtrak Passenger Train 371 and Norfolk Southern Railway Company Freight Train 23M Chicago,
Illinois, November 30, 2007

Passenger Fatality on Long Island Rail Road, Queens, New York, August 5, 2006, (DCA-06-FR-009)

BNSF Railway Company Remote Control Locomotive Switching Operation Fatality Stockton, CA August 30, 2007

Derailment of CSX Transportation Train No. Q39010, Oneida, New York, March 12, 2007

Collision of Two Union Pacific Railroad Trains, Bertram, California, November 10, 2007

Derailment of Norfolk Southern Railway Company Train 68QB119 with Release of Hazardous Materials and Fire
New Brighton, Pennsylvania October 20, 2006

Collision of Two Southeastern Pennsylvania Transportation Authority Trains, Abington, PA, July 1, 2006
Collision
of Norfolk Southern Freight Train 192 With Standing Norfolk Southern Local Train P22
With Subsequent Hazardous Materials Release at Graniteville, South Carolina, January 6, 2005
Just some highlights…..

NEXT GENERATION TRAIN CONTROL
- PTC
Locomotive centric train control system with:
Onboard (on the locomotive) equipment
 Wayside signal equipment
 Communications (data)
 Back office servers

WHAT DOES A PTC SYSTEM DO?

Delivers movement authorities to onboard display

Uses track data, GPS and locomotive systems to identify location and track
elements

Warns train operators of unsafe operations

Automatically enforces movement authorities and speed restrictions, and

Sends thousands of messages across a secure, reliable communication
system
What Does PTC Do- Electronic Delivery
The Track Database, Train Clearance, Bulletins and Track Authorities are sent
electronically for display to the engineer. This data is used by PTC to
generate Warnings and Enforcement.
GPS
TRAIN
DATA
I-ETMS
BOS
TRAIN
DATA
CAD
ACKNOWLEDGEMENT
PASSING SIDING
WORK
ZONE
25 MPH
INDUSTRY SIDING
39
PTC SEGMENTS
Wayside
Segment
Office Segment
Dispatch
PTC Back
Office
Server
Monitored
Control
Points
M03
Message
Router
Monitored
Switches
Asset
Tracking System
Communications
Segment
Locomotive
Segment
Other
Monitored
Devices
PTC COMMUNICATION SYSTEM
PTC RADIOS
Locomotive Radio
74VDC / 50W
Base Radio
24/48 VDC / 75W
Wayside Radio
12VDC / 30W
GIS FOR PTC
Critical Features
• Signals
• Points of Switches
• Clearance Points
• Mile Markers
• Limits of Road Crossings at Grade
• Limits of Permanent Speed
Restrictions
• Sign locations
+ 200 attributes of these and other
features
NS
Where Is
PTC Going?
Per the FRA
approved PTCIP,
NS will need to
deploy PTC on
10,904 miles of its
railroad
All main lines
 Carrying > 5MGT
traffic, any amount
of TIH*
 Over which any
passenger or
commuter travels
* TIH traffic 2012 NPRM
44
NS Internal
COST
Railroad
PTC investment through 2011
ARR
$29,000,000
BNSF
$482,481,000
CN
$43,435,000
CP
$37,000,000
CSX
$333,000,000
KCS
$32,500,000
NS
$265,000,000
UP
$335,000,000
Total
$1,557,416,000
$20 cost to RR
for every $1
safety benefits
Alternative risk
reduction: Areas ripe for
benefits at lower costs
 Track caused
accidents account for
34% of mainline
accidents
 Equipment caused
accidents account for
26% of mainline
accidents
RR INDUSTRY – WHY PTC?
A BNSF coal train collided with the rear end of a standing BNSF MOW
train near Red Oak, Iowa. Both the engineer and conductor of the coal
train were fatally injured. Contributing to the accident was the
absence of a positive train control system that identifies the rear of
a train and stops a following train if a safe braking profile is exceeded.
"Humans are fallible and make mistakes and operational
accidents can be prevented with positive train control," NTSB
Chairman Deborah Hersman said.
QUESTIONS?
Railway Infrastructure
and Train Control
presented to - CE 433
University of Kentucky