A Primer On Railroad SignalsA Primer On Railroad Signals

A Primer on Railroad SignalsDick JohannesMarch 1313, 201010/22/20101

The variety of signalsseems endlessdl10/22/20102

Keyy historical events 1840: Ball signals:gLTC Rolt1841: Semaphore – Charles Gregory1851:Telegraph – Chas Minot1870: Track Circuit – William Robinson1871: Disk (Banjo) Signal – Thomas Hall1904: ColorClight signals – William ChurchillC1915: Position-light signals – Arthur Rudd1920: Searchlight Signals – Hall Signal CoCo.1924: Color Position signals – Frank Patenall1925: TriTri-colorcolor (G type) signals - GRS10/22/20103

Signals:g3 keyyqquestions1. What degree of prototypeaccuracy can do you want toachieve?2. What era and region are youmodeling?3. How much can yyou afford?10/22/20104

Two typesyp of “regions”gInterlockings & JunctionsBlock ABlock BBlock CBlock DBlock EBlock FBlock GLinear Blocks10/22/20105

The Distinctions Linear blocks––––Unsupervised (e.g. totally automated)Default is “clear” or “green”ABS (Automated Block Signaling)APS (Absolute Permissive Signaling) Interlockings (Junctions & Sidings)–––––Manually operated (e.g. human controlled)Default is “stop”p or “red”Mechanical interlocksUS&S panelsComputerized CTC10/22/20106

ABSTime 0Time 1Time 2Time 3Time 410/22/20107

ABS - weaknessTime 0Time 1Time 210/22/20108

APBDispatcher clears this train10/22/20109

The “OS” sectionDummyHeadDummyHead10/22/201010

AspectpCombinatoricsUPPER HEADLOWER HEADASPECTGREENGREEN281GREENYELLOWNot RED285REDGREEN283REDYELLOW290REDRED291

Aspects:pNORAC*10/22/2010Rule: 281Name: ClearIndication: Proceed notexceeding Normal SpeedRule: 281cName: Limited ClearIndication: Proceed at LimitedSpeed until entire train clearsall interlocking or springswitchesRule: 281aName: Cab SpeedIndication: Proceed inaccordance with cab signalindicationRule: 282Name: Approach MediumIndication: Proceedapproaching the next signal atMedium SpeedRule: 281bName: Approach LimitedIndication: Proceedapproaching the next signalat Limited SpeedRule: 282aName: Advance ApproachIndication: Proceed prepared tostop at the second signal.Trains exceeding Limited Speedmustt reducedtot LimitedLi it d SpeedSdas engine passed the signal* 9th Edition, 2008- Flashing12

Aspects:pNORAC* (cont)()Rule: 283Name: Medium-ClearIndication: Proceed at MediumSpeed until entire train clearsall interlocking or springswitches,stc es, tthene pproceedoceed atNormal SpeedRule: 285Name: ApproachIndication: Proceed prepared tostop at the next signal. Reduceto Medium Speed as enginepasses signalRule: 283aName: Medium ApproachMediumIndication: Proceed at MediumSpeed until entire train clearsall interlocking or springswitches, then approach nextsignal at Medium SpeedRule: 286Name: Medium ApproachIndication: Proceed ppreparedptostop at the next signal. Reduceto Medium Speed as soon assignal is clearly visibleRule: 287Name: Slow ClearIndication: Proceed at SlowSpeed until entire train clearsall interlocking or springswitches,it hthenth proceedd attNormal SpeedRule: 284Name: Approach SlowIndication: Proceedapproaching the next signalat Slow Speed10/22/2010* 9th Edition, 2008- Flashing13

Aspects:pNORAC* (cont)()Rule: 288Name: Slow ApproachIndication: Proceed at SlowSpeed until entire train clearsall interlocking or springswitches,stc es, tthene pproceedoceed atMedium SpeedRule: 292Name: Stop SignalIndication: StopRule: 290Name: RestrictingIndication: Proceed at RestrictedSpeed until entire train clears allinterlocking or spring switchesand leading wheels have 1)passed a more favorable signal or2) entered non-signaled territory.Rule: 296bName: Speed Limit SignIndication: Proceed at speedpposted on the Approach SpeedLimit Sign until entire train haspassed the Resume Speed SignRule: 291Name: Stop and ProceedIndication: Stop then proceed atRestricted Speed until leadingwheels have 1) passed a morefavorable signal or 2) enterednon-signaled territory10/22/2010* 9th Edition, 2008- FlashingSRRule: 296cName: Resume Speed SignIndication: Resume speed afterentire train has passed theResume Speed Sign14

The Modeler’s AspectspRule: 281Name: ClearIndication: Proceed notexceeding Normal SpeedRule: 285Name: ApproachIndication: Proceed prepared tostop at the next signal. Reduceto Medium Speed as enginepasses signal10/22/2010Rule: 292Name: Stop SignalIndication: StopRule: 290Name: RestrictingIndication: Proceed at RestrictedSpeed until entire train clears allinterlocking or spring switchesand leading wheels have 1)passed a more favorable signal or2) entered non-signaled territory.15

Create a linear schematic10/22/201016

Create a linear schematic10/22/201017

Create a linear schematicPortlandE. DeerfieldSpringfieldTo BostonTo SelkirkGardnerAyerWorcester Label blocks Label signals (Name east/west or north/south) What’s CTC and what’s block trackage between CTC10/22/201018

Three keyiimplementationlt ti questionsti What is the incoming information neededand how do I get it? How do I process the incomingi finformation?ti ? How do I output the processedinformation?10/22/201019

Inputsp Where are my trains?What direction are they moving?Wh t ttrainWhati iis it?How are my turnouts set?10/22/201020

DetectionIsolated fromTrack PowerReliabilityModification ofRolling StockCostR dSReedSwitchesit hYYesF iFairYYesHi TNoVery GoodYesMediumInductionYesVery GoodYesLowMethod10/22/201021

Processingg Hardware–––––Logic RailCustom Signals (Atlas)Integrated Signal SystemsCircuitronDallee Software––––JMRICMRIRailroad & CoSignals by Spreadsheet10/22/201022

Outputsp Strictly hardware– Gets complex and expensive with morecomplex track plans– Less flexible Hardware and Software– More flexible– RequiresRiprogrammingi ((somehow)h )10/22/201023

Controllingg the SystemyScreen shot fromDick Bronson’sHartford NationalClinics10/22/201024

CATS10/22/201025

Controllingg the SystemyLUSERVILLESHAFERS CROSSINGHAROLDTONENGLUND CENTRE10/22/201026

Controllingg the SystemyLUSERVILLESHAFERS CROSSINGHAROLDTONENGLUND CENTRE10/22/201027

Controllingg the SystemyLUSERVILLESHAFERS CROSSINGHAROLDTONENGLUND CENTRE10/22/201028

Controllingg the SystemyLUSERVILLESHAFERS CROSSINGHAROLDTONENGLUND CENTRE10/22/201029

The double saw-byyAspect?10/22/201030

Choices Ignore interlockings and just do ABS/APS Just do 1 or a few interlocks and ignorethe “blocks”blocks in between How long is a block?– 3 average train lengths?– 100 scale feet? How many aspects? Dark areas? How do you handle them?10/22/201031

Consider emulation Block or signal animators– Logic rail– Circuitron Just use Red/Green indications for R/Npositioniti att tturnoutst Will look pretty good and unless you areactually using them to operate may suffice10/22/201032

Appassingg sidingg6 detectors10 Signals16 signal heads to illuminate2 tortoises and DCC decoders10/22/2010 78 340 199 60 67733

The Future?C b SignalsCabSil Leg up for the modern modeler? NoNo fixed signals Location, direction & speed DCCDCC throttles with LCDs BiDirectional DCC Could stopp locomotive10/22/201034

References (Books)() Railroad Signaling. Brian Soloman, MBI Publishing 2003.How to operate your model railroad. Bruce A Chubb, 2nd Edition,Kalmbach, 1977.Realistic Model Railroad Operation.pTonyy Koester. Kalmbach 2003.The Model Railroaders Guide to Junctions. Jeff Wilson. Kalmbach2006.Railroader’sRailroaders Handbook Volume 2 Signaling SystemsSystems. Version 3 Dr.DrBruce A. Chubb. 2010 available through CMRI websiteRailroad Operation and Railway Signaling. Edmund J Phillips.Simmons-BoardmanSimmonsBoardman 1942Compendium of Signals. Roger F.R Karl. Boynton, 1971.All About Signals. John Armstrong, Kalmbach, 1967.10/22/201035

References ((Web Sites)) Carsten Lundstens site: http://www.lundsten.dk/us signaling/index.htmlNorac Simulator: ailroad Signals: http://www.railroadsignals.net/Railroad Signals of the US: http://www.railroadsignals.us/http://www railroadsignals us/JMRI: http://jmri.sourceforge.net/CATS: http://home.comcast.net/ kb0oys/CMRI http://www.jlcenterprises.net/CMRI:htt //jltit/Custom Signals: http://www.customsignals.com/ISS: http://www.integratedsignalsystems.com/Signals by Spreadsheet: http://www.signalsbyspreadsheet.com/Railroad Circuits: http://rr-cirkits.com/Logic Rail: http://www.logicrailtech.com/http://www logicrailtech com/10/22/201036

References (Journals)() Operating signals with software. Model Railroader, October 2007,page 50.50The Computer/Model Railroad Interface - A Case Study. ModelRailroading, December 1999/January 2000, page 32.Using State-of-the-art Electronics to Enhance Operation. NMRABulletin, March 2007 page 38.Signaling made easier (3 part article). Model Railroader, January2004, page 130.Automated Block Signaling using DCC Signal Driver Decoders. ModelRailroading, July 2006, page 28.Absolute-Permissive Block Signals (3 part article). Model Railroader,November 1991 page 128.Where to pplace trackside signalsgon a model railroad. ModelRailroader, October 2007, page 52.10/22/201037

THANK YOU10/22/201038

A Primer on Railroad SignalsA Primer on Railroad Signals Dick Johannes March 13 2010March 13, 2010 10/22/2010 1. The variety of signals seems endless 10/22/2010 2. . Indication: Resume speed after entire train has passed the Resume Speed Sign R 10/22/2010 14 wh