WABCO TAILGUARD User manual

TAILGUARD™
FOR REFUSE COLLECTION VEHICLES

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Table of contents

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Table of contents
Table of contents
1 Introduction ...................................................................................................................................................... 4
2 Safety information............................................................................................................................................ 6
2.1 General safety instructions ...........................................................6
2.2 Summary of the safety instructions from the chapters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 TailGUARD™ .................................................................................................................................................. 10
3.1 TailGUARD™ for trailers ............................................................10
3.2 TailGUARD™ for Truck & Bus ........................................................10
4 TailGUARD™ for refuse collection vehicles ............................................................................................... 11
4.1 General functional principles .........................................................11
4.2 Why use TailGUARD™ and not a camera system? .......................................13
4.3 RetrottingTailGUARD™:Requirementsfortherefusecollectionvehicle......................13
5 Required components: Overview ................................................................................................................. 15
5.1 Variant:Onlymonitoringandwarning ..................................................15
5.2 Variant:Autonomousbrakingviaseparatevalves .........................................16
5.2.1 Separate valves for vehicles with an ABS braking system...................................................... 17
5.2.2 Separate valves for vehicles with a conventional braking system........................................... 18
5.2.3 Separate valves for vehicles with an EBS braking system...................................................... 18
5.3 Variant:AutonomousbrakingviaapreparedinterfaceforTailGUARD™ .......................19
6 Installation of the ultrasonic sensors .......................................................................................................... 20
6.1 The three standard applications ......................................................21
6.2 Positioningofthesensorsonrefusecollectionvehicles ....................................22
6.3 Testingthesensorpositions .........................................................25
6.4 Protectionagainstdamage ..........................................................26
6.5 Cablerouting .....................................................................27
7 Connecting TailGUARD™ to the vehicle electrical system ....................................................................... 30
7.1 Variant:Onlymonitoringandwarning ..................................................31
7.2 Variant:Autonomousbrakingviaseparatevalves .........................................32
7.2.1 Actuation of the stop lights ...................................................................................................... 33
7.2.2 Connecting with the electrical compartment............................................................................ 33
7.2.3 Interface connector.................................................................................................................. 34
7.3 Variant:AutonomousbrakingviaapreparedTailGUARD™interface ..........................35
8 Installation of the separate valves ............................................................................................................... 36
9 Planning and performing the TailGUARD™ installation ........................................................................... 38
Edition 1
Version 1 (05.2017)
815 010 212 3 (en)
Thispublicationisnotsubjecttoanupdatingservice.
Youwillndthecurrentversionat:
http://www.wabco.info/i/675

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Introduction Introduction
1 Introduction
ThisdescriptionismainlyintendedforpersonswhowanttoplantheinstallationofTailGUARD™inrefusecollection
vehiclesandcarryouttheinstallation.
TailGUARD™isasystemformonitoringtheareabehindvehicleswhichisautomaticallyactivatedwhenreversegear
isengaged.TailGUARD™wasinitiallydevelopedfortrailers.Thesystemisalsoinstalledontowingvehiclesand
busesformonitoringtheareabehindthevehiclewhenreversingwiththeaidofultrasonicsensors.
Ifthesystemdetectsanobstacleintheintendedpathoftravel,itacousticallyandopticallyindicatesthedistanceto
thedriver.Whenthevehiclereachesadenedminimumdistancetotheobject,thevehiclecanbestoppedbyan
automaticactuationofthebrakingsystem.
Refuse collection vehicles frequently in reverse gear
Thesystemisparticularlyusefulonrefusecollectionvehiclessincetheyareoftenforcedtocopewithbothshorterand
comparativelylongdistancesinreversegear,forinstanceincul-de-sacswherethereisinsufcientspaceforturning
around.Insituationslikethis,thedriverhastonegotiatelongerdistancesoverwhichheispartiallyunsightedwhen
lookingintherear-viewmirrors.Thismeansthathemayoverlookobstaclesintheroadorpeoplecrossingoverbehind
therefusecollectionvehicle.
Another special scenario: constant presence of people in the area
behind the vehicle
Thereisanotherimportantreasonforinstallingareversemonitoringsystem.Inthecaseofmostrefusecollection
vehicles,peopleareconstantlyworkingbehindthevehiclewhohavetomanoeuvretherefusecontainerstothe
respectiveliftingandtippingmechanism,andthenhookthemintopositionbeforetheyareliftedandemptied.Itoften
happensthatrefusecollectionscannotstopthevehicleintimeduetocarelessnessorasuddenhealthimpairment.
Thisregularlyresultsinseriousaccidentsandseveraldeathseveryyear.Thiscanbepreventedtoalargeextentby
installingTailGUARD™asareversemonitoringsystem.

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Introduction
Special challenges with refuse collection vehicles
Incontrasttoconventionaltowingvehiclesorbuses,mostrefusecollectionvehicleshaveprotrudingliftingandtipping
mechanismsandotherauxiliarydevicesttedtothebackofthevehicle.Thiscanmakeitdifculttondsuitable
locationsforinstallingtheultrasonicsensors.Forinstance,therefusecollectiondevicesonthebackofthevehicle
mustnotbewronglyidentiedasbeingobjectsintheareabehindthevehicle.Thesensorsmustalsobeinstalled
withespeciallyeffectiveprotectionsothattheyarenotdamagedduringthedailyrigoursofcollectingrefuse.Despite
allthesefactors,theymustbeabletoreliablysensethemonitoringareabehindthevehicle.Furtherchallengesarise
withthecablerouting.Here,itmustbeconsideredwhatmovementsaremadebytheattacheddevicesforllingand
emptyingthevehiclesothatthesensorcablescanberoutedinacorrectmanner.
Thisdescriptioncontainsimportantinformationexplaininghowyoucanmasterthesechallenges.

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Safety information
2 Safety information
2.1 General safety instructions
Observe all required provisions and instructions:
Readthispublicationcarefully.
Adheretoallinstructions,informationandsafetyinformationtoprevent
injurytopersonsanddamagetoproperty.
WABCOwillonlyguaranteethesafety,reliabilityandperformanceoftheir
productsandsystemsifalltheinformationinthispublicationisadheredto.
Alwaysabidebythevehiclemanufacturer'sspecicationsandinstructions.
Observeallaccidentregulationsoftherespectivecompanyaswellas
regionalandnationalregulations.
Make provisions for a safe work environment:
Onlytrainedandqualiedtechniciansmaycarryoutworkonthevehicle.
Usepersonalprotectiveequipmentifrequired(protectivegoggles,
respiratoryprotection,earprotectors,safetyshoes).
Pedalactuationscanleadtosevereinjuriesifpersonsareinthevicinityof
thevehicle.Makesurethatpedalscannotbeactuatedasfollows:
Switchthetransmissionto"neutral"andactuatethehandbrake.
Securethevehiclewithbrakewedges.
Fastenavisiblenotetothesteeringwheelindicatingthatworkisbeing
performedonthevehicleandthatthepedalsarenottobeactuated.

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Safety information
Avoid electrostatic charge and uncontrolled discharging (ESD):
Noteduringconstructionandbuildingthevehicle:
Preventpotentialdifferencesbetweencomponents(e.g.axles)andthe
vehicleframe(chassis).
Makesurethattheresistancebetweenmetallicpartsofthe
componentsandthevehicleframeislessthan10ohms.
Establishanelectricallyconductiveconnectionbetweenmovingor
insulatedvehicleparts,suchasaxles,andtheframe.
Preventpotentialdifferencesbetweenthetowingvehicleandthetrailer.
Makesurethatanelectricallyconductiveconnectionismadebetween
metalpartsinthetowingvehicleandthecoupledtrailerviathecoupling
(kingpin,fthwheel,clawswithpins),evenwithoutacablebeing
connected.
Useelectricallyconductiveboltedconnectionswhenfasteningthe
ECUstothevehicleframe.
Runthecablewithinmetalliccasingswherepossible(e.g.insidethe
U-beam)orbehindmetalandgroundedprotectiveplatingtominimise
theinuenceofelectro-magneticelds.
Avoidtheuseofplasticmaterialsiftheycancauseelectrostatic
charging.
Whilecarryingoutrepairorweldingworkonthevehicle,observethe
following:
Disconnectthebattery(ifinstalledinthevehicle).
Disconnectcableconnectionstodevicesandcomponentsandprotect
connectorsandportsagainstcontamination.
Alwaysconnectthegroundingelectrodedirectlywiththemetalnextto
theweldingpointwhenweldingtopreventmagneticeldsandcurrent
owviathecableorcomponents.
Makesurethatcurrentiswellconductedbyremovingpaintorrust.
Preventheatinuencesondevicesandcablingwhenwelding.

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2.2 Summary of the safety instructions from the chapters
Observe the following safety instructions for interventions in the braking system:
Observethespecicationsofthevehiclemanufacturer.
Deactivationwhenthesupplypressureistoolow:Switchthesystemoffif
thevehicle'ssupplypressureistoolow.
Onlyintervenewiththebrakingsystemifyouhavesufcientknowledgeof
thebrakingsystemandknowandcantakeresponsibilityfortheeffectof
youractionsandalltheirconsequences.
Thebrakingsystemisunderpressure.Beforeinterveningwiththebraking
system,makesureallreservoirsandlinesarepressureless.
Withbrakinginterventionsvia separately installed valves,thefrontaxle
mustnotbebraked.Makesurethatthevehicle'sfrontaxlecanNOTbe
brakedbythesystem.Brakinginterventionmustonlyoccurviatherear
axle(s).
To avoid any accidents, observe the following safety instructions for vehicles with braking intervention
through TailGUARD:
Becausethestoppingdistancebecomeslongerwithheavilyladenvehicles
-inparticularwhenitisequippedwithEBS-thesettings(parameter
setting/pressurelimitingvalve)mustenablesufcientdecelerationforthe
fullyladenvehicle.
Notepulsedbrakingwhenreversingtoofast:
TailGUARDcanassistonlywithreversingspeedsbelowmax.9km/h.
TailGUARDwilltriggershortbrakepulseswhenacriticalspeedis
reachedtoalertthedriver.
Ifthedriveracceleratesfurther,TailGUARDdeactivatesitselfand
outputsafaultmessage.
InthecaseofEBSvehicleswithbrakeinterventionvia separately
installed valves, ABSfunctionsarenotavailableduringTailGUARD
braking.EvenatthelowspeedrangeatwhichTailGUARDisactive,the
wheelsmightlockonslipperysurfaces.
Speedsignalfaultsduetoincorrectorunprofessionalconnectioncan
signicantlyimpairvehiclesafety.
Vehicles with a prepared interface for TailGUARD: TailGUARD may not
brakeifthevehicle’sEBSsystemhasafault.
Safety information

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Observe the following safety instructions for handling cables:
Waterthatentersthecablecoreorcablesleevecandamageelectronic
controlunits.Cableswithopenendsshouldthereforealwaysbe
connectedinthedriver’scabtoensurethatnowatercanenterthem.
Wherethisisnotpossible,useasuitablecablejointbox,e.g.AK190.This
applies in particular when using the prepared brake interface on the
Daimler Econic Euro6.
Planyourinstallationpositionsothatcablescannotbecomekinked.
Fastenthecablesandconnectorssothattheplugconnectionsarenot
subjectedtoanytensilestressorlateralforces.
Neverroutecablesoversharpedgesorinthevicinityofaggressivemedia
(e.g.acids).
Routethecabletotheconnectionssothatnowatercanenterthe
connector.
Fastenthecabletiessothatthecableisnotdamaged.
Whenusingtools,pleasenotetheinstructionsofthecable-tie
manufacturer.
Ifthecablesaretoolong,donotwindthemupbutlaytheminloops.
Observe the following safety instructions for handling ultrasonic sensors:
Thesurfacetowhichtheultrasonicsensorismountedmustbeevenand
mustbeatleast2mmlargerthantheultrasonicsensor(thisisrequired
toprotectthedrainageholesintherearagainstdirecthigh-pressure
cleaning).
UltrasonicsensorsmustnottobemountedinaU-prolebecausethis
couldcausereections.WABCOrecommendstomounttheultrasonic
sensorsmechanicallyprotectedtoavoiddamage.
Theabilitytodetectobjectslargelydependsontheultrasonicsensors'
positioningonthevehicle.Makesurethattheultrasonicsensorsare
installedataheightofatleast40cm.
Noothervehiclecomponentsshouldbeinstalledwithintheultrasonic
sensor'srangeofvision.
Therateofdetectiondependsonobjectsurfaces:
Ultrasoundisbestreectedbysmoothsurfacesthatarepositionedata
rightangletothesound'sdirection.
Smallandunfavourablesurfacessuchasmeshedstructures,furry
orhairysurfacesatanobliqueangletothesound'sdirectionarenot
detected so easily.
Safety information

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3 TailGUARD™
3.1 TailGUARD™ for trailers
TailGUARD™wasinitiallydevelopedfortrailervehiclesttedwithanEBSbrakingsystemandusedonthe
trailer.Incidentally,thisexplainswhythetrailersuseEBSEdiagnosticsoftwarefordiagnosingandconguringall
TailGUARD™systemsandputtingthemintooperation,evenwhereTailGUARD™isinstalledinthetowingvehicle
orbus.Thediagnosticsoftwareautomaticallydetectsthiswhenthesystemstartsupandswitchestotheappropriate
mode.
TwodifferentsystemsareavailablewithTailGUARD™fortrailervehicles:
WithTailGUARDlight™,twoultrasonicsensorsareusedtomeasuretheactualdistancetotheloadingramp.The
systemdoesnotmonitortheentireareabehindthevehicle,butisonlyanaidforapproachingtheramp.
TheotherthreeTailGUARD™variantsaresystemsformonitoringtheareabehindthevehicle.WABCO
recommendsaminimumsystemofthreesensorsonthesamelevel(thevariantTailGUARD™).Withthe
TailGUARDROOF™variant,forexample,aroofovertherampcanbedetectedbytwoextraultrasonicsensors
mountedonanadditionalupperlevel.Arearareamonitoringsystemcanberealisedwiththeaidofsixultrasonic
sensorsontwolevels(TailGUARDMAX™)whichisalsocapableofdetectingsmallerobjectsbehindthevehicle.
ThemostdetaileddescriptionofTailGUARD™fortrailervehiclescanbefoundintheTEBSEsystemdescription.You
candownloadthelatestversioninWABCOINFORMundertheproductnumber8150100933.
3.2 TailGUARD™ for Truck & Bus
WithTailGUARD™fortowingvehiclesandbuses,thesamesensorisusedforthetrailervehicleswhichisusedto
monitortheareabehindthevehicle.Themostsignicantdifferenceconcernshowthesystemisintegratedinthe
vehicleelectricalsystem,andhowanautomaticbrakingactionisrealisedwhentheconguredminimumdistanceto
anobstacleisreached.
Here,TailGUARD™forTruck&Bussupportsvariouspossibilities,whichareconciselyexplainedinthisdescription.
Adetaileddescriptionofthesystem,togetherwith
amoreprecisedescriptionoftheoverallsystem,
alistanddescriptionoftherequiredcomponents,
installationinstructions,
adescriptionofhowthesystemisputintooperation,
operationbythedriver,
maintenanceanddiagnosisinstructionsforworkshops,
aswellaswiringdiagrams,
canbefoundinthesystemdescriptionforTailGUARD™forTruck&Bus.Youcandownloadthelatestversionin
WABCOINFORMundertheproductnumber8150102113.
Note:AnycrossreferencesgiveninthissystemdescriptionofTailGUARD™forTruck&Busthatrefertospecic
placesrelatetoversion3ofthissystemdescription.
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11
4 TailGUARD™ for refuse collection vehicles
4.1 General functional principles
To avoid any accidents, observe the following safety instructions for
vehicles with braking intervention through TailGUARD:
Vehicles with a prepared interface for TailGUARD: TailGUARD may not
brakeifthevehicle’sEBSsystemhasafault.
ThegeneralfunctionalprinciplesofthesystemcorrespondtothoseofTailGUARD™forTruck&Bus:
TailGUARD™isactivatedwhenreversegearisengaged.
Theareabehindthevehicleisthenmonitored(dependingontheapplication)bybetweentwoandsixultrasonic
sensors.Themaximumnumberofultrasonicsensorsthatcanbeinstalledprimarilydependsontherespective
liftingandtippingdevicesttedtotherefusecollectionvehicle.
ThesensorsignalsaretransmittedoveraseparateLINbustotheElectronicExtensionModule,whichisanintegral
partofthesystem,andthenprocessedthere.
Withregardtotheremainingscopeofthesystem,therearethreevariants:
•First variant:Ifthesystemisonlytobeusedasavisualdisplaytoalertthedriverwhenanobjectisdetected
intheareabehindthevehicle,anysuchobjectswithinthedetectionareaofthesensorsareindicatedbyLEDs
arrangedinbarsontheTrailerRemoteControldisplayandinputunit:
TailGUARD™ for refuse collection vehicles

12
TailGUARD™ for refuse collection vehicles TailGUARD™ for refuse collection vehicles
Here,
– threegreenLEDsstandfordistancesbetween450and300cm,
– threeyellowLEDsstandfordistancesbetween300and150cm,
– andthreeredLEDsstandfordistancesbetween0and150cm.
– TheredLEDsalsohavetwodifferentstates:
▪IfthecorrespondingLEDashes,thedistanceisabout50cm.
▪IftheLEDlightsupcontinuously,thedistanceisapprox.25cmorless.
TheTrailerRemoteControlalsoemitsacousticsignalsviaabuilt-inbuzzer.Similartoparkingaidsfamiliarfrom
passengercars,thissignalisemittedatevershorterintervals,throughtoacontinuoustone,whenapproaching
anobjectbehindthevehicle.
Note:Thedisplayandcontrolunitiscalleda"TrailerRemoteControl"becauseitwasintroducedwith
TailGUARD™fortrailervehicles,andbecausehereitistheidenticalunit.Inthisconguration,however,the
devicehasnothingtodowithtraileroperations.
Incertaincountries,objectsbehindthevehiclecanalsobedisplayedbyacorrespondingashingofthe
vehicle'srearoutlinemarkerlampsinsteadofviatheTrailerRemoteControl.
•Second variant:Usually,itisreasonablyrequiredthatthesystem–inadditiontothedisplayandwarning
function–alsoautomaticallystopsthereversingvehiclewhenitreachesacertainpreconguredstopping
distance.Forthispurpose,thevehicleisautonomouslybrakedviaadditionallyttedpneumaticvalves.These
valvesarecontrolledbytheElectronicExtensionModule.
Theamountofcontrolledbrakingpressureisalsodependentupontheactualvehiclespeedsothatthestopping
distancecanbeadheredtosafely.Forthisreason,theElectronicExtensionModulereceivesthespeedsignal
fromthevehicleviaacorrespondingconnectioncable.
TheElectronicExtensionModulemustalsobeconnectedtothevehicleelectricalsystemwithotherspecial
cables,forexampletocontrolthestoplightsduringanautonomousbrakingaction.
•Third variant:Here,autonomousbrakingiseffectedbythevehicle'sownservicebrakeratherthanwiththeaid
ofseparatelyttedvalves.
Todothis,thevehiclemanufacturermusthaveinstalledacorrespondingelectronicTailGUARD™interface,
viawhichtheElectronicExtensionModulecansendtherequiredbrakingrequirementstothevehicle'sbraking
system.
Thisfunctionisavailablefrom2017asaspecialoptionforsometowingvehiclesproducedbyMercedes-Benz.
Here,theElectronicExtensionModuleisconnectedwiththreespecialcablestotheinterfaceprovidedbythe
manufacturer.Thisallowstheexchangeofotherinformation,suchasthevehiclespeed,thedrivingdirection,
andthedistancetoobjectsbehindthevehicle.
Withthisthirdvariant,thefunctionalreadinessofthesystemandthedistanceinformationareindicatedonthe
displayonthevehicle'sinstrumentpanel.Theacousticwarningissoundedviathealreadyttedspeakers.This
obviatestheneedfortheTrailerRemoteControl.

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TailGUARD™ for refuse collection vehicles
4.2 Why use TailGUARD™ and not a camera system?
Atrstglance,acamerathatprovidesthedriverofarefusecollectionvehiclewithanopticalimageoftheareabehind
thevehiclewouldappeartobesuperiortotheultrasonic-baseddetectionprincipleusedbyTailGUARD™.
Oncloserconsideration,however,TailGUARD™offersdecisivebenets,particularlywhererefusecollectionvehicles
areconcerned:
Acamerasystemrequiresgoodlightconditions.Adequatelightingisonlyavailableduringdaylighthours,however.
TailGUARD™,ontheotherhand,alwaysfunctionsequallywellwhatevertheconditions:indaylight,atdawnand
dusk,andeveninthedark.
Withacamerasystem,whilereversingthedrivermustalwayskeepaneyeonboththemonitorwiththedetailed
cameraimageandtherear-viewmirror.Thisdividedattentioncreatesadditionalstress,andcanleadtomistakes
inrecognisingthesituationbehindthevehicle.WithTailGUARD™,aswellasasimpleopticalsignal,thedriveris
alertedbyadditionalacousticwarningsignals.Thisenablesthedrivertovisuallyfocusontherear-viewmirror.
Withacamerasystem,thedrivermusthimselfidentifyanyrelevantobjectsinthecameraimage.The
TailGUARD™systemautomaticallyrecognisesbothmovingandstationaryobjects.
TailGUARD™alsodetectsandmeasuresthedistancetoobjectsintheimmediatevicinityoftherearofthevehicle,
andindicatesthedistancesbetweenthem,whichissomethingthatcamera-basedsystemsarenotcapableof.
Withacamerasystem,thedriverhastoactivelydecidewhentobrakeandthenperformtheaction.TailGUARD™
ontheotherhand,canautonomouslybrakethevehiclewhenitapproachesanobject.
Whilethecamerasopticsneedtoberegularlycleaned,TailGUARD™doesnotrequireanymaintenance.
4.3 Retrotting TailGUARD™: Requirements for the refuse
collection vehicle
Herearethemostessentialrequirementsthathavetobefullledbythevehicle:
Suitablelocationsforinstallingtheultrasonicsensors:
• Itcanbeaproblemwithrefusecollectionvehiclestondsuitableinstallationlocationsfortheultrasonicsensors
dependingontheinstalledliftingandtippingsystem.
• Generally,however,atleasttwosensorscanbesuccessfullyinstalledandconguredinsuchawayasto
providesatisfactorymonitoringoftheareabehindthevehicle.
• Inextremecases,however,specialrear-mountedsuperstructuresmaymeanthatitisnotpossibletouse
TailGUARD™formonitoringtheareabehindthevehicle.Incaseofdoubt,itisthereforeadvisabletocheck
theinstallationpossibilitiesbyconductingtestsbeforehandtopinpointsuitablepositionsforthesensors(see
Chapter 7).
Supplyvoltage:
• Allvehicleswitha24Vsupplyvoltagecanbettedwiththesystem.
• Vehicleswitha12Von-boardelectricsystemcanonlybettedwiththesystemifapermanentsupplyvoltageof
more than 11.5 V is assured.

14
Typeofbrakingsystem:
• ConventionalbrakingsystemwithoutABS:thevehiclecanbettedwithTailGUARD™.Inthiscase,thebraking
pressuregeneratedseparatelybyTailGUARD™isfedintotheinputoftherelayvalveortheautomaticload-
dependentbrakepowerregulator(LSVcontroller).
• VehiclewithABS:TailGUARD™isapprovedforallABSsystems.
• VehiclewithEBS:
– TailGUARD™isapprovedforvehiclesttedwithWABCOEBS.
– Forvehicleswithnon-WABCOEBS,aconversionbeforehandtoWABCOEBSisrecommended.
Speedsignal:
• AspeedsignalinaccordancewithISO16844-2(C3signal)mustbeprovidedinthevehicle.
• Thevehiclemanufacturermustnothaveprohibiteduseofthissignalforexternalsystems.
Expertapproval:
• Ifthevehicleistobebrakedautonomouslywhenapproachingobjectsbehindit,andifitisbeingoperatedin
publicareas,itmustbeinspectedbyanexpertaftertheconversion(atleastinEurope)incompliancewiththe
ECE-R13standard.
• AbasicexpertassessmentisavailablefromWABCOwhichconrmsconformitywithECE-R13providedthe
systemisinstalledcorrectly.Thismeansthatitisthenonlynecessarytohavetheindividualvehicleinspected
byanexpertforcorrectinstallation.
MoredetailedinformationregardingtherequirementsforthevehiclecanbefoundinChapter4ofthesystem
description for TailGUARD™ for Truck & Bus.
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15
5 Required components: Overview
ThischaptergivesanoverviewofthecomponentsthatarerequiredforthefollowingthreeTailGUARD™variants.
FurtherdetailscanbefoundinChapter6ofthesystemdescriptionforTailGUARD™forTruck&Bus.
To avoid any accidents, observe the following safety instructions for vehicles with braking intervention
through TailGUARD:
Becausethestoppingdistancebecomeslongerwithheavilyladenvehicles
-inparticularwhenitisequippedwithEBS-thesettings(parameter
setting/pressurelimitingvalve)mustenablesufcientdecelerationforthe
fullyladenvehicle.
Notepulsedbrakingwhenreversingtoofast:
TailGUARDcanassistonlywithreversingspeedsbelowmax.9km/h.
TailGUARDwilltriggershortbrakepulseswhenacriticalspeedis
reachedtoalertthedriver.
Ifthedriveracceleratesfurther,TailGUARDdeactivatesitselfand
outputsafaultmessage.
InthecaseofEBSvehicleswithbrakeinterventionvia separately
installed valves, ABSfunctionsarenotavailableduringTailGUARD
braking.EvenatthelowspeedrangeatwhichTailGUARDisactive,the
wheelsmightlockonslipperysurfaces.
Speedsignalfaultsduetoincorrectorunprofessionalconnectioncan
signicantlyimpairvehiclesafety.
Vehicles with a prepared interface for TailGUARD: TailGUARD may not
brakeifthevehicle’sEBSsystemhasafault.
5.1 Variant: Only monitoring and warning
IfTailGUARD™isonlytobeusedformonitoringandwarningpurposes(seeSection4.1,rstvariant),thefollowing
componentsarerequired:
2to6ultrasonicsensorsdependingonyourownrequirements,aswellasthenumberofinstallationlocationsthat
arepossibleontherefusecollectionvehicleinquestion.
TheappropriateextensionandsplittercablesforconnectingtheultrasonicsensorstotheElectronicExtension
Module.
TheElectronicExtensionModule(alsoreferredtohereastheECU),whichcontainsthecontrolelectronicsand
providesalltherequiredsocketsfortheconnectingcables.TheECUisusuallymountedontheframeofthe
vehicleascloseaspossibletothedriveaxle.TheECUmustalwaysbeinstalledsothatthecableopeningspoint
downwardsortotheside.
ATrailerRemoteControlinthevicinityofthedriver'sseatforopticalandacousticindicationofthedetected
distances,aswellasforwarningpurposes.TheTrailerRemoteControlalsoallowsthedrivertomanuallyadjustthe
volumeoftheacousticindicatorandtotemporarilydisableTailGUARD™.
AspecialsupplycableforthepowersupplytotheECU,whichisfedtoterminals15,30and31inthefuseboxor
thevehicle'selectricalcompartment.TheTrailerRemoteControlisalsoconnectedtoterminals15and31ofthis
linelinktosupplyitwithvoltage.Inaddition,theTrailerRemoteControlcommunicateswiththeECUviathisline
usingthePLCmethod:"PowerLineCommunication"usesapowersupplylinetosimultaneouslytransmitelectrical
signals.
Required components: Overview

16
AGIOcable,withwhichtheECUtapsthepowersupplyforthereversinglight.Thisenablesthesystemto
detectwhenreversegearisengaged,sothatitthenactivatesthemonitoringoftheareabehindthevehiclewith
TailGUARD™.
Adiagnosticsocket.Thisisinstalledinaneasilyaccessiblepositionoutsideofthevehicleandisconnectedto
theECUwithitscable.Thediagnosticsocketisusedforconguringthesystem'sparametersandputtingitinto
operation,aswellasfordiagnosingmalfunctions.
Additionaloptionalcomponents,suchasamonitoringoff-switch,anextrabuzzerandindicatorlamps,canbe
connectedtoadditionalGIOsocketsintheECU.
5.2 Variant: Autonomous braking via separate valves
Withthisvariant,thefollowinglinelinksarerequiredinadditiontotheprecedingvariant:
AcableviawhichtheECUreceivesthevehiclespeedsignal.Thiscableisroutedeitherdirectlytothevehicle
tachograph,ortoaninterfaceprovidedbythevehiclemanufacturerinaccordancewithISO16844-2("C3signal",
alsocalleda"B7signal").Theothercablewiresarenotusedandmustbeisolated.Thespeedsignalisrequiredby
theECUinordertobeabletomatchtheappliedbrakingpressuretotheactualspeedofthevehicle.
Otherwiresoftheuniversalcable(whichisonlyusedwiththerstvariantfortappingthepowersupplyto
thereversinglight)areusedtoconnectthetwostoplightssothattheycanbesuppliedwithpowerduringan
autonomousbrakingaction.
Whichadditionalvalves,sensorsandlinelinkshavetobeinstalledsothatanautonomousbrakingactioncanbe
executedwhenapproachinganobjectbehindthevehiclewilldependuponthebrakingsystemofthevehiclein
question.ThisishowthesystemfunctionsonvehiclesequippedwithanABSbrakingsystem:
Required components: Overview

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5.2.1 Separate valves for vehicles with an ABS braking system
Whenthedriveractuatesthebrakingvalve(2)onatowingvehicleequippedwithanABSbrakingsystem,thebraking
pressurefortherearaxlereachesthecontrolinputoftheLSVregulator(9),whichthenadaptsthebrakingpressure
totheloadstatusofthevehicle.ItsoutputpressurereachestheTristopcylindersattherearaxleviathetwoABS
solenoidvalves(10).
Toadditionallyenableautonomousbrakingactions,thestandardcongurationofthispartoftheABSbrakingsystem
isextendedwithTailGUARD™asfollows:
Supplypressurefortherearaxleispassedonviaabranchlinetoanappropriatelysetchargingvalve(3).The
effectofthisisthatautonomousbrakingisonlypossibleatasufcientsupplypressureofatleast7.3bar.
Fromhere,thepressurereachesapressurelimitingvalve(4).Thismakesitpossibletosetthemaximumbraking
pressurethatcanbegeneratedforanautonomousbrakingaction.Inthecaseofrefusecollectionvehicles,a
maximumbrakingpressureofapprox.3.8barhasfrequentlyprovedtobemosteffective.
Thebrakingpressurethenpassesthroughtwosolenoidvalves(5)and(6)thatareconnectedinseries.Theseare
controlledbytheECU(1),andenablemodulationofabrakingpressurethatisadaptedtothevehiclespeed.The
seriescircuitensuresthatthevehicleisonlybrakedwhenbothvalvesareactuated.Thispreventsanautonomous
brakingactionfrombeingtriggeredduetoanelectricalfault.
ThemodulatedbrakingpressureisfedintothecontrolinputoftheLSVregulator(9)viaatwo-wayvalve(7).From
here,theoutputpressurereachestheTristopcylindersoftherearaxleintheusualmanner.Thebrakingpressure
isalsomeasuredbyapressuresensor(8)thatislikewiseconnectedtotheECU(1).
Required components: Overview

18
5.2.2 Separate valves for vehicles with a conventional braking system
OnvehiclesequippedwithLSVregulatorsbutwithoutanABSsystem,autonomousbrakingiseffectedinthesame
mannerasforvehiclesttedwithanABSbrakingsystem.Inthesystemdiagram(see4.2.1),onlythetwoABS
solenoidvalves(10)aremissing.
OnvehicleswithaconventionalbrakingsystemwithoutanLSVregulator,theoutputpressureisinsteadfedintothe
controlinputoftheconventionalrelayvalveviaatwo-wayvalve.
5.2.3 Separate valves for vehicles with an EBS braking system
Whenthedriveractuatesthebrakesignaltransmitter(notshownhere)onatowingvehiclewithanEBSbraking
system,thebrakingpressureisapplieddirectlytotheTristopcylindersfromtheoutputsoftheaxlemodulator(2)inthe
usual manner.
Required components: Overview

19
Toenableancillaryautonomousbrakingactions,theadditionalvalvesfamiliarfromtheABSbrakingsystemare
installed.Thereareonlytwomaindifferences:
Here,theoutputtedbrakingpressureisnotforwardedtoanLSVregulatorbecauseitstaskistakenoverbytheaxis
modulator.Instead,thebrakingpressureisfedtothecontrolinputofanadditionallyinstalledrelayvalve.Thetask
ofthisvalveistoshortentheresponsetimeoftheautonomousbrake.
TheoutputpressureoftherelayvalvethenreachestheTristopcylindersoftherearaxleviathetwolikewise
additionallyinstalledtwo-wayvalves(7).
5.3 Variant: Autonomous braking via a prepared interface for
TailGUARD™
To avoid any accidents, observe the following safety instructions for
vehicles with braking intervention through TailGUARD:
Vehicles with a prepared interface for TailGUARD: TailGUARD may not
brakeifthevehicle’sEBSsystemhasafault.
Withthisvariant,separatevalvesdonothavetobeinstalledbecausetheautonomousbrakingactionsareeffected
usingtheexistingEBSservicebrakesystemofthetowingvehicle.
Dependingontheinterfacetothetowingvehicle,theopticalindicationscanbeshownonthedisplayonthevehicle's
instrumentpanel.Hardwarecanalsobeinstalledinthedriver'scabbythevehiclemanufacturerfortheacoustic
signalling.Otherwise,aTrailerRemoteControlcanbeusedhereaswellforopticalandacousticindicationpurposes.
Withthisvariant,theECUisconnectedtotheTailGUARD™interfacettedthevehiclemanufacturerbyfourmulti-core
connectingcables.Theseareused,amongotherthings,
tosupplypowertotheECU,
totransmittherequestsignalfortheautonomousbrakingaction,
toreporterrorstates,
andforconnectingtheECUtothecorrespondingon-boardCANbus.
OntherstavailablevehicleserieswithanoptionallypreparedTailGUARD™interface,theMercedes-BenzEconic
Euro6,thevehicleinterfacecomprisesthreemulti-pinsocketsX1,X2andX3.Thecorrespondingthreeconnector
housingsneedtobeobtainedfromthevehiclemanufacturer,andarethenttedwiththefourconnectingcables
suppliedbyWABCO.
Otherwise,theECUisconnectedtoadedicateddiagnosticsocketaswiththeothertwovariants.
Required components: Overview

20
6 Installation of the ultrasonic sensors
Observe the following safety instructions for handling ultrasonic sensors:
Thesurfacetowhichtheultrasonicsensorismountedmustbeevenand
mustbeatleast2mmlargerthantheultrasonicsensor(thisisrequired
toprotectthedrainageholesintherearagainstdirecthigh-pressure
cleaning).
UltrasonicsensorsmustnottobemountedinaU-prolebecausethis
couldcausereections.WABCOrecommendstomounttheultrasonic
sensorsmechanicallyprotectedtoavoiddamage.
Theabilitytodetectobjectslargelydependsontheultrasonicsensors'
positioningonthevehicle.Makesurethattheultrasonicsensorsare
installedataheightofatleast40cm.
Noothervehiclecomponentsshouldbeinstalledwithintheultrasonic
sensor'srangeofvision.
Therateofdetectiondependsonobjectsurfaces:
Ultrasoundisbestreectedbysmoothsurfacesthatarepositionedata
rightangletothesound'sdirection.
Smallandunfavourablesurfacessuchasmeshedstructures,furry
orhairysurfacesatanobliqueangletothesound'sdirectionarenot
detected so easily.
Installation of the ultrasonic sensors