VG Rope Brake (VGRB2) · The VG rope brake does not require an external power source to generate...

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VG Rope Brake (VGRB2)Operation and Installation Manual

Version 3.0

1VG Rope Brake (VGRB2) Version 3.0

Contents

Handle

Disc Springs

Front Plate

4 X M12 ScrewsUndo to split the rope brake

Front CoverElectrical Connecting PlugSafety Switch, Electromagnetic Power Supply and Earth Connections

M16 Threaded for mounting bracket

Fixed Jaw

Back Plate

Drop Jaw

Overview ....................................................................................................................2

Braking Capacity ........................................................................................................3

Rope Factors ..............................................................................................................4

Gripping Elements .....................................................................................................4

Control Requirements ...............................................................................................5

• 6a–RB2controlbox • 6b–UMD-SRB01controlbox

EnquiryForm(Example) ............................................................................................6

BrakeselectionProgram(Example)..........................................................................7

InstallationoftheVGropebrake ..............................................................................8

DrawingTD-RB4 ........................................................................................................9

Installation VGRB2 ...................................................................................................10

Installation VGRB2 ...................................................................................................11

DimensionsVGRB2–singlebrakeunit ...................................................................12

DimensionsVGRB2–duplexedbrakeunits ...........................................................13

DimensionsVGRB2–withUMD-SP01sensorunit .................................................14

WiringDiagram–RB2ControlBox .........................................................................15

WiringDiagram–UMD-SRB01ControlBox ............................................................16

VGropebrakewithRB2HandWindingInstructions ..............................................17

VGropebrakewithUMD-SRB01HandwindingInstructions ................................18

Maintenance ............................................................................................................19

TypicalInstallationofVGropebrakeandUMD-SRB01 ..........................................20

MountingBracketDesign ............................................................................... 21&22

AdjustingtheRopeBrake .......................................................................................23

FrequentlyAskedQuestions ...................................................................................24

2 AtwellInternationalLimited

To Reset the VG rope brake after engagement.

1. Turn key switch to rest

2. Slacken 4 x M12 screws (19mm spanner) 3. Pivot handle back until magnet re-‐ latches 4. Retighten 4 x M12 Screws (no torque setting

required) 5. Turn Key switch back to RUN.

4 x M12 screws

Handle

Moving Jaw

Fixed Jaw

TheVGropebrakewasdesignedbyDrDSCameronin2002forAtwellInternationalLtd.Theropebrakewasre-designedin2007toenableittooperateinabi-directionalmodeandtoimprovemanufactureandassembly.However,theessentialoperatingprinciplesremainunchanged.TheVGropebrakeiscoveredbyUKpatent2314070andis“CE”certifiedbyBSI.

Thebrakeoperatesontheliftropesandisdesignatedasa“movementprevention”or“speedreducing”meansincompliancewithEN81-11998clause9.10.TheVGropebrakecombinestheproventechnologyof“drop-jaw”typegovernorswiththepatentedVGlinkagemechanism.ThebrakeoperatesinasimilarmannertoaVGsafetygearexceptthatithasonefixedjawandonemoveablejawor“drop-jaw”.

Thedrop-jawisspring-loadedbytwotorsionspringsbutisheldclearoftheliftropesbyaDCelectro-magnet.Threestrengthsoftorsionspringareavailabletosuitthemountingpositionandapplicationoftheropebrake.Thedrop-jawisreleasedbyanover-speedgovernororotherapprovedmeanssuchasthe“UncontrolledMovementDetector”(UMD-SRB01)availabledirectlyfromAtwellInternationalLtd.Whenthebi-directionalVGropebrake(VGRB2)isusedinconjunctionwiththeUncontrolledMovementDetector(UMD-SRB01)fullcompliancewithbothEN81-11998clause9.10andBSEN81-80:2003significanthazardnumber53andclause5.9.4.canbeachieved.WhenusedinconjunctionwitheithertheUMDorVGOSGwillalsocomplywithEN81-1:1998+A3:2009.

Whenthedrop-jawisreleased,theliftropesaretrappedbetweenthemovingandstaticjaws.Anysubsequentmovementoftheliftropescausesthedrop-jawtofullyengageandgeneratethebrakingforce.Theropecontactpressureiskepttoaminimumsoasnottodamagetheliftropes.

Thebrakeincorporatesasafetycontactforinclusionintothesafetycircuitoftheliftcontrolsystem.Untilthebrakehasbeeninspectedandreset,theliftcannotbeputbackintoservice.Thebrakeisresetbyhandwindingtheliftmotoruntilthedrop-jawreleaseswherebyitcanberesetmanuallyusingthein-builthandle.

Ifhandwindingisnotpossible,thenthedrop-jawassemblycanbereleasedbyslackeningthefourM12x25HexHeadexternalscrewssecuringthemovingjawassemblytothesideplates.Theboltscanthenbere-tightenedafterthejawhasbeenreset.

Overview

Turn key switch on UMD to reset.

Slacken 4 x M12 screws (19mm spanner) on front of the rope brake (green washers)

Turn key switch on UMD to reset.

Turn key switch on UMD Back to run.


Tocontrolupwardfallingorpreventuncontrolledmovement,aVGropebrakemust generate a minimum dynamic braking force equal to the Out of Balance Load(OBL)oftheliftsystem.AnyresidualbrakingforceinexcessoftheOBLwilldeceleratetheliftcar.

TheVGropebrakeusesgrooveandfrictionformulaegiveninEN81tocalculatethetheoreticalstaticanddynamicforces.Theformulaearebasedontheropespeedandthegrooveprofileofgrippingjaws.

The permitted friction values are considered conservative and the braking forces are likely to be slightly higher than calculated.

Thedecelerationoftheliftwilldependonthemagnitudeoftheresidualbrakingforce,thetotalkineticenergyoftheliftsystemandanysystemlosses.

It is recommended that the dynamic braking force of the VG rope brake should be between two or three times the OBL of the lift system. This will provide a gentle and controlled deceleration of the lift without imposing high forces on the lift structure or damaging the lift ropes.

Toassistropebrakeselection,aspreadsheetprogramhasbeenpreparedtocalculatethetheoreticalstaticanddynamicbrakingforceforthegrooveprofileandspringforceselected(seepage7).Toensurethecorrectropebrakeconfigurationisselected,itisessentialtheenquiryform(seepage6)iscompletedasaccuratelyandascomprehensivelyaspossible.

Forcomparisonpurposes,theprogramalsocalculatestheropepressuregeneratedbya35degree“V”groovetractionsheavehavingthesamenumberandsizeofropes.

Thebrakingforceiscontrolledbythejawgeometryandthespringstackselectedusingtheapplicationprogramreferredtoabove.

Thetablebelowhasbeenpreparedforaliftwitharopespeedof1.5m/sec,a50%balanceandadynamicbrakingforcebetween2and3timestheOutofBalanceLoad(OBL).Thetableisindicativeonly.

DiscSpring BrakingForce-Newtons ContractLoad“Q”kg

Thickness Static Dynamic Maximum Minimum

2.0 mm 7160 6110 630 423

2.5 mm 12374 10554 1000 630

3.0 mm 16282 13886 1250 800

Braking Capacity


Theoretically,aVGropebrakecanbetailoredtosuitanyropespeed.Todatethebrakehasonlybeentestedonropespeedsupto5m/sec.

Theoreticalcalculationshaveproventhathigherspeedscanbeachievedbutwillresultinmoreropeslideandathigherropecontactpressure.

Thestandardropejawshaveamaximumwidthof150mm.Thiswillpermitamaximumof6ropesof13mmdiameterwithapitchof21mm.However,specialjawscanbesuppliedtosuitotherropingarrangements.

TheVGropebrakewillworkwithbothfibreandsteelcoredropes(steelcoreropesarepreferredasthesecanwithstandhigherclampingforces)ofallconstructiontypesandcanbeinstalledwithoutthenecessitytore-rope.

ItisrecommendedthatnewropesarefittedwheninstallingaVGropebrakeforthefirsttime.However,VGropebrakescanbefittedtoexistingropesprovidedthesearecheckedforsizeandwearbeforefittingtheropebrake.

Itisalsoessentialthattheropesarecorrectlyalignedandpitchedalongtheirentirelength,aropegathererfittedtotheliftropesabovethecounterweightmayberequiredinordertoachievethis.

Rope Factors

Thestandardgrooveprofileforthejawsisanundercut,semi-circulargroove.Thispermitsthemaximumbrakingforceforthelowestropecontactpressure.Thewidthoftheundercutcanbeoptimizedforeachapplicationusingtheapplicationprogram.Iftheundercutistoonarrowtoallowthebraketoself-generate,theprogramwilladviseincreasingthegroovewidth.

Thejawsarecasehardenedtoreducewearandareexpectedtowithstandnumerousfullspeedtestsbeforetheyneedreplacing.Whenoperatingtoprevent“uncontrolledmovement”,thenumberofoperationswillbegreater.

Themaximumrecommendedropecontactpressureis25N/mm2.Thisrepresentsa50:1safetyfactorofthetensilestrengthoftheropewirematerial.

Gripping Elements


TheVGropebrakedoesnotrequireanexternalpowersourcetogeneratethebrakingforce.

AVGropebrakewillprovidethe“speedreducing”meansasrequiredinclauses9.10and9.11.4ofEN81-1:1998+A3:2009.The“speeddetection”meansisprovidedbyabi-directionalover-speedgovernor(VGOSG)orotherapproveddevices.Whenoperatingwithanover-speedgovernor,theVGropebrakeutilisestheauxiliarycontactsonthesafetyswitchtoreleasetheDCelectro-magnet.

Theropebrakecanalsobeusedtopreventanyformofuncontrolledmovementwhenoperatedbyasuitablecontroldevicesuchasthe“UMD-SRB01”detector.

RB2

Forthepreventionofoverspeedinginthe“up”directiononly1VGropebrakeisrequiredandtosimplifyinstallation,testingandmaintenance,itisrecommendedthattheVGropebrakeisoperatedbythecontrolunitRB2.Thisunitincorporatesabatteryback-upcircuittopreventspuriousoperationshouldthepowerbedisconnectedforwhateverreason.ThiswillkeeptheVGrope-brakedisengagedandfullyoperationalforaminimumof3hours.

Thecontrolunitincorporatestestbuttonsandindicatorlightstofacilitateroutinemaintenanceandinspection.

UMD-SRB01 – Uncontrolled Movement Detector

TheUMD-SRB01connectstothemainliftcontrolpanelandwillprovidepowerandbatterybackupfor2xVGropebrakesforaminimumof3hours.Fromhereitcanreceivepowerandsignalstotelliftheliftdoorsareopen,orthatthemainsafetycircuitisOKanddetectoverspeedconditions.

TheUMD-SRB01detectsmovementbymeansofaropesensorsystemthatcanbebolteddirectlytothetopoftheVGropebrakesoasthecarmovesthewireropesattachedtoitalsomovesandsorotatesthepulleywhichisconnectedtoa4channelencodersystem.

Whenthedoorsareopenthesystemischeckingforexcessivemovement.Excessivemovementoftheliftwhenthecar/landingdoorsareopenisfactorysetto150mm+/-30mm,butcanbeadjustedfrom0mmto900mm+/-30mmasrequired.IfexcessivemovementisdetectedthentheVGropebrakesunderitscontrolwillbedeployedandinadditiontothisanemergencystopsignalwillbesenttothemainliftcontrolpanel,thisisbymeansofinterruptingthemainsafetycircuit.

OverspeedsignalscanbedetectedfromeithertheoverspeedgovernorortheropesensorsystemandondetectionwilldeploytheVGropebrake.

Control Requirements


Enquiry Form (Example)


Brake selection Program (Example)

Atwell Interna tional Limited

Bi-Directional VG Rope Brake

VGRB2 - Documentation Page 7 of 21 Version 1.0 24/01/2008

Ball Mill Top Business Park, Hallow, Worcester, WR2 6PD, United Kingdom

Tel: +44 (0) 1905 641881 Fax: +44 (0) 1905 641298 Email: [email protected]

8. Brake selection Program (Example)

Atwell International Job Reference W707/077

Customer Reference Lygon Street

Lift system variables Data Units Comments

Lift capacity "Q" 630 kg

Car mass "P" 1000 kg

Car load balance 50 %

Counterweight mass 1315 kg

Lift speed 1 m/sec

Roping ratio 1 enter 1 for 1:1; 2 for 2:1

Rope speed 1 m/sec

Number of ropes 4

Rope diameter "d" 13 mm

Rope pitch 21 mm

Spring Stack Configuration 4 Enter number 1 to 9

Spring Thickness 2.5 mm

Number of Disc Springs 5

Number of spacers 4

Groove data - undercut "U" groove Length of jaws 115 mm

percentage of groove undercut 50%

Width of undercut 6.5 mm Select groove width from chart

Rope Brake Clamping Force "F" 34200 Newtons

Rope contact area per jaw 5342 mm2

Contact pressure between rope and jaws 13.1 N/mm2

Rope Pressure on Traction Sheave 9.3 N/mm2 35

o "V" groove on 40:1 D:d ratio

Static Braking Force 11137 Newtons

Dynamic Braking Force 9988 Newtons

Force to overcome Out of Balance Load (OBL) 3090 Newtons

Dynamic Braking Factor "k" 3.23

Static Braking Factor "k" 3.60

Lift machine and motor data

Sheave Diameter 560 mm

Gear Ratio of drive unit 36

Motor Nominal Speed 1228 rpm

Motor and wormwheel inertia 0.05 refer to manufacturer's data

Flywheel inertia 0.15

Total high speed inertia 0.20 kgm2

Rotational speed of motor/flywheel etc 129 Rads/sec

Kinetic energy of motor/flywheel 1653 Nm

Kinetic energy of lift car and counterweight 1158 Nm

Kinetic energy of ropes, cables and pulleys 289 Nm

Total kinetic energy to be dissipated 3100 Nm

Dynamic Performance of Brake Residual Braking force to overcome Kinetic Energy 6898 Newtons

Deceleration of lift ropes 1.11 m/sec2

Rope slide through brake at lift speed 449 mm

Rope slide through brake at governor tripping speed

594 mm

Car slide at governor tripping speed 594 mm Governor Electrical tripping speed 1.15 m/sec Time of test 0.90 secs


TheVGropebrakeshouldbeinstalledusingbracketswhichwillfacilitateaccuratealignmentandadjustmentofthebrakesothatitisbothparallelandsquaretotheliftropes.Thebracketsmustbecapableofwithstandingthestaticbrakingforcecalculatedbytheapplicationprogramwithanappropriatemarginofsafety.

ItisrecommendedthattheVGropebrakeislocatedclosetothelifttractionsheaveordivertersheave(s).Itshouldbeinstalledwithaminimumclearancebetweenthestaticjawandtheliftropes.

Theminimumdistancebetweenthecentre-lineofthesheaveandthetopoftheropebrakejawis400mmwithamaximumclearanceof1mm.Asthedistancefromthesheaveisincreased,therunningclearancemaybeincreasedtoamaximumof 5mm(seefigureTD-RB4,page9).

Abi-directionalarrangementcanbelocatedbetweenthetractionanddivertersheaveprovidedthedistancebetweenthesheaveswillpermitthis.Thebrakesmustbefittedwiththecorrecttorsionspringtosuittheangleofinclination“A”.Abi-directionalarrangementcanalsobefittedtoeitherthecarorcounterweightsideorsingle“down”brakestobothcarandcounterweightropesasillustratedabove.

Singleropebrakesareonlyfittedtopreventoverspeedinthe“UP”directionandshouldbeusedinconjunctionwitha“DOWN”actingsafetygear.Whenusedinthisapplicationtheropebrakeshouldbefittedinapositionthattheropesaremovinginadowndirectionthroughtheropebrakejawswhenthecounterweightisalsomovinginthedowndirection.

Installation of the VG rope brake

Down direction of single rope brakes

Bi-directional arrangement consists of one brake for the “Down” direction and one brake for the “Up” direction

“Down” Brake

“Up” Brake

A


TD-RB4


Installation VGRB2

Fig. 1 – As Delivered.

Liftthedropjawandfitthe“yellow”plasticremovablestoptothebackofthedropjaw.

Thiswillpreventthejawsbindingduringtheinstallation.

Fig. 2 – Splitting the rope brake

Usingthesupplied19mmspannerundoandremovethe4xM12HexHdScrewsandsplitthedropjawassemblyfromthefixedjawassembly.

Fig. 3 – Duplexing the rope brake

Usingthesuppliedjoiningplateduplexthe2ropebrakefixedjawassemblies.

EnsurethattheJawserialnumber“TAXXX”matchesthejawserialnumberonthedropjawassemblyandtheyareassembledasshownwiththedownbrakeonthetop.

Fit removable stopDrop Jaw

Fixed Jaw Assembly

Drop Jaw Assembly

M12 x 25mm Hex Head Screws

Down Brake

Jaw Serial Number Stamped here “TA XXX”

Joining Plate

M16 ct/sk screws

Up Brake

M16 Studs


Installation VGRB2

Fig. 3 – Attaching mounting plates

Attachthemountingsideplatesasperthe installation’s requirements.

TheVGropebrakeissecuredtoitsmountingbracketsby4xM16screws.Each screw must react on half of thebrakingcapacityoftheVGropebrake.Basedonashearstressof100N/mm2,themaximumbrakingforcethesecanreacttois31.4kN.

Manymountingoptionsareavailablefrom Atwell International on request.

Fig. 4 – Fitting to the ropes

PositiontheassemblyaroundtheropesinaccordancewiththedrawingTD-RB4shownonpage9.

Fixthemountingplatesinpositionandsecure.

Theropebrakewillimposeadynamicloadonthefloororsteelworkofonly15%ofthestaticload.

Fig. 5 – Completed Assembly

Reattachthe2xDropJawassembliesensuringthejawserialnumbersmatchtherespectivefixjawassemblies.

Removethe“yellow”plasticstops.

ConnecttheelectricalleadsfromeithertheRB2orUMD-SRB01controlboxestotheelectricalplugonthefront.

Powerupthecontrolbox,liftthedropjawandcheckthemagnetholdsitclear of the ropes.

Mounting Side Plate (Example)

M16 Full NutM16 Spring WasherM16 flat washer

Traction ropes

Fix to existing floor or machine room steels

Down Brake

Electrical Connection Plug

M12 Hex Hd Screws

Up Brake

Removable Stop


Dimensions VGRB2 – single brake unit

Weight per rope brake = 24kgWeight of each standard side plate = 2kg

Standard Side Plate

Pivot handle back to enable the jaws to reset. Do not pull up vertically.


Dimensions VGRB2 – duplexed brake units

Weight of above assembly = 56kg

Pivot handle back to enable the jaws to reset. Do not pull up vertically.


Dimensions VGRB2 – with UMD-SP01 sensor unit

100mm dia drive wheel

Traction Ropes

UMD-SP01

Sensor mounting plate

Sensor mounting bracket

2 x M6 x 16 mm screws with spring and flat washers per bracket

Sprung loaded tension bolts

Electrical connection plug

Tensioning Bolt Arrangement

M5 lock nut

M5 washer

Sensor plate

Spring

Support plate

M5 washer

M5 washer

M5 Skt screw x 55 mm

Alternative Tensioning Bolt Arrangement


Wiring Diagram – RB2a Control Box


Wiring Diagram – UMD-SRB01 Control Box


VG rope brake with RB2 Hand Winding Instructions

VG Rope Brake InstalledDisengage Before Hand Winding Machine

RELEASE INSTRUCTIONS

1. INVESTIGATEREASONFORENGAGEMENTANDCARRYOUTAPPROPRIATEACTION.

2. CARRYOUTVISUALINSPECTIONOFROPEBRAKE.

3. READLOCALHANDWINDINGINSTRUCTIONS.

4. HANDWINDINTHEDOWNWARDTODIS-ENGAGETHEROPEBREAK.

5. TURNKEYSWITCHTO“RESET”POSITION.

6. SLACKEN4XM12SCREWSWITHGREENWASHERSONTHEFRONTFACEOFTHEDROPJAWASSEMBLY.

7. USINGROPEBRAKEHANDLELIFTDROPJAWFREEOFROPES.

8. CHECKLED’S1,2,3&4AREILLUMINATED.

9. RE-TIGHTEN4XM12SCREWSWITHGREENWASHERSONTHEFRONTFACEOFTHEDROPJAWASSEMBLY.

10.TURNKEYSWITCHTO“RUN”POSITION.


VG rope brake with UMD-SRB01 Hand Winding Instructions

Bi-Directional VG Rope Brake Installed

Disengage Before Hand Winding

RELEASE INSTRUCTIONS

1. Checkthevisualdisplaysonthe“UMD-SRB01”controlbox.

2. CarryoutvisualinspectionoftheVGropebrakes,checkingwhichbrakehasfullyengaged.

3. Investigatereasonforengagementandcarryoutappropriateaction.

4. Readlocalhandwindinginstructions.

5. Onthe“UMD-SRB01”controlpanelinsertthekeyandturntothe“RESET”position.

Note:Anaudiblealarmwillsounduntilthekeyisreturnedtothe“Run”position.

6. Onthedeployedbutnotfullyengagedropebrake,usingtheropebrakehandlere-engagethedropjawwiththeelectro-magnet.Checkthe“ROPEBRAKESET”LEDislitonthe“UMD-SRB01”controlpanel.

7. Handwindthemachineintheoppositedirectionoftheengagementforapproximately25mm.Thiswillfreethedropjawfromtheropes.

8. Usingtheropebrakehandlere-engagethedropjawwiththeelectro-magnet.Checkthe“ROPEBRAKESET”LEDislitonthe“UMD-SRB01”controlpanel.

9. Continuefollowingthelocalhandwindinginstructionsforthegearedmachine.

NOTE:Ifnopowerandthebatterybackuphasfailed,releasethedropjawandinserttheplasticmechanicalstopstothebackofthedropjaw.

TO RE-INSTALL LIFT SERVICE FOLLOWING HAND WINDING

1. EnsurebothropebrakesareresetandthecorrespondingLEDsonthe“UMD-SRB01” are lit.

2. Ensurethereasonforengagementhasbeeninvestigatedandappropriateactiontaken.

3. Turnkeyswitchbackto“RUN”positionandremovekey.

4. Check lift is working correctly.


Maintenance At6monthlyintervals,thefollowingchecksshouldbecarriedout-

1) the“dropjaw”shouldbereleasedandthebrakecheckedthattheropesarebeingclampedbetweenthe“dropjaw”andthestaticjaw.

2) thatthetopofthe“dropjaw”isbetween10and12mmabovethetopofthestaticjawwhenthe“dropjaw”isreleased.Ifthe“dropjaw”islessthan10mm,thiscouldindicatethateithertheropesor“dropjaw”haveworn.Wornjawswillhavetobereplaced.

A limited amount of rope wear can be accommodated by re-setting the rope brake as per instructions on page 23. This should be carried out by a competent person. Please contact the manufacturers (Atwell International) should this need to be done.

3) thattheropebrakesafetyswitchhasoperated,thiscanbedonebyreleasingtheelectro-magnetandcheckingthattheredLEDonthecontrolboxisilluminated.

4) thatthe“dropjaw”linkagemovesfreelywhenoperatedbyhand.

5) Ensuretheback-upbatteryisatasufficientcharge.Notethebatteryrequireschanging after 3 years from installation.

ContactAtwellInternationalLtdforanyspares.

Theonlymaintenancerequiredistospraythelinkarmsandthediscspringswithawaterrepellentlubricantifthereisanysignofatmosphericcorrosion.


Typical Installation of VG rope brake and UMD-SRB01

Item No. Description Comments

*1 UMD-SRB01ControlBox Suppliedwithwallmountingbracketsandfixings

*2 ElectricalConnectionHood 32mmconduitfittings

*3 ConnectionCabletoDownBrake Pre-wiredtoconnectionsocketoneend(5mtrslong)

*4 ConnectionCabletoUpBrake Pre-wiredtoconnectionsocketoneend(5mtrslong)

*5 ConnectionCabletoUMD-SP01 Pre-wiredtoconnectionsocketoneend(5mtrslong)

*6 UMD-SP01 MovementSensorPackandMountingBracket

*7 VGropebrake“Down” SuppliedwithJoiningPlateandfixingsorstandardsideplatesandfixings

*8 VGropebrake“Up” SuppliedwithJoiningPlateandfixings

9 Side(angle)mountingplates Variousoptionsavailableonrequest

10 MountingPlate Variousoptionsavailableonrequest

11 Connections to Lift Control Panel Customerconnections(seepage13)

12 TractionSheave Existingequipment

13 MachineBedplate Existingequipment

14 MachineRoomSteels Existingequipment

15 DiverterSheave Existingequipment

16 Traction Ropes Existingequipment

*Items1–8aresuppliedasstandardwhenorderingabi-directionalVGropebrakewithuncontrolledmovementcontrol.


Mounting Brackets Design Calculations

TofacilitatetheinstallationoftheVGropebrake,AtwellInternationalcan providemountingplatesandsideplates.Thesebracketsaredesignedinaccordancewiththeliftinstallationandareverifiedbyuseofthefollowingprogrammeandinconjunctionwithdrawing“BI-DIRECTIONALMOUNTINGBRACKETDESIGN–FILE2ROPE6”.

Calculated result for thickness of base plate

Alternative design


Bi-Directional Mounting Bracket Design “FILE 2ROPE6”


Adjusting the rope brake to allow for rope wear

THIS PROCEDURE SHOULD ONLY BE CARRIED OUT BY A COMPETENT PERSON FOLLOWING DISCUSSION WITH ATWELL INTERNATIONAL OR ITS APPOINTED REPRESENTATIVE

Whenassembledandadjustedcorrectly,thedrop-jawmustclamptheropeswhenitis10to12mmhigherthanthestaticjaw.Thisisspecifiedasdimension“h”infigureTD-RB7.Thiswillensurethattheropebrakewillself-actuatewhenthedrop-jawisreleased.Toachievethis,proceedasfollows:-

1. Onthetopropebrakeonlylowerthedropjawontheropesandmeasuretheheight“h”whenclampingtheropes.Ifthisisoutsidetherange10to12mm,adjustthesettingnuts,oneflatatatimeinrotationuntilthisisachieved.

NB: tightening the setting nuts will reduce the height “h”. Conversely, slackening the nuts will increase the height. To determine how many turns to adjust the setting nut, please refer to the chart

Forexample,if“h”measures16mm,subtract2.4mmfrom3.2mm(thesettingdimensionat11mmminusthesettingdimensionat16mm)togiveadifferenceof 0.8 mm.

Aturnofoneflatofthesettingscrewswillmovethenut0.25mm.Therefore,eachnutwillneedtobetightenedby3flatstoreducetheheightto11mm.

2. Whenadjustedcorrectly,markeachnutandsealwithredpaint.

The dimension “h” should only be changed by altering the setting nuts located inside the terminal box.

Dim “h”Setting (mm)

25 0

24 0.3

23 0.6

22 0.9

21 1.2

20 1.5

19 1.7

18 2.0

17 2.2

16 2.4

15 2.6

14 2.8

13 2.9

12 3.1

11 3.2

10 3.4

9 3.5

8 3.6

7 3.7

Correct Setting Height

Remove front cover to expose 4 x M18 adjusting nuts


Frequently Asked Questions

Will the VG rope brake damage the ropes?

No.ItwasafundamentalrequirementthattheVGropebrakedidnotcauseanysignificantdamagetotheropes,evenafterrepeatedtestingonthesameinstallation.Aftertesting,allthatisevidentisa“polishingaway”oftheropelubricantwherethejawshavecontactedtherope

Will the VG rope brake impose additional reactionary loads on to the machine room floor or steels?

No.Machineroomfloorsandsteelworkmustbedesignedtotakeadynamicloadequaltothestaticloadofthelift,i.e.twicethestaticload.TheVGropebrakewillimposeadynamicloadonthefloororsteelworkofonly15%ofthestaticload.

Which control unit should be used with the VG Rope Brake?

Iftheropebrakeistobeusedtoarrestoverspeedinthe“UP”directiononly,thenthecontrolbox“RB2”shouldbeused.

IftheropebrakeistobeusedtoarrestoverspeedandpreventmovementoftheliftcarineitherdirectionwiththedoorsopenthenthecontrolboxUMD-SRB01shouldbeused.Pleaserefertothe“OperationandmaintenanceManualfortheUncontrolledMovementDetector”forfurtherinformation.

What is the minimum space required between the centre line of the ropes and the machine room wall/upstands?

Theminimumdimensionfromtheropebrakebackplatetothecentrelineoftheropesis38mm.Pleaserefertothedimensioneddrawingsonpage12and13formoredetailedinformation.

What is the maximum capacity of the rope brake?

TheVGropebrakehasbeentestedforliftspeedsupto5m/sec.Thisisregardlessofthemassoftheliftcar,theVGropebrakeonlyhastobraketheOutofBalanceLoadandnotthefullmassoftheliftsystem.Theeffectofdifferentcarandmotormassesistochangetheslidedistance.Seebrakeselectionprogramonpage7.

What is the voltage and wattage of the electro– magnet?

Thestandardvoltageforthebrakecoilis12VoltsDC.Othervoltagesareavailabletospecialorder.Thepowerconsumptionofthestandardcoilisonly4watts.

Other quality products available from Atwell International:

BallMillTopBusinessPark,Hallow,Worcester,WR26PD,UnitedKingdomTel.:+44(0)8712270470Fax:+44(0)1905641298Email:[email protected]

Copyright©2008AtwellInternationalLimited.Allrightsreserved.

VG Rope Brake (VGRB2) · The VG rope brake does not require an external power source to generate...

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Transcript of VG Rope Brake (VGRB2) · The VG rope brake does not require an external power source to generate...