WABCOinform.wabco-auto.com/intl/pdf/815/000/314/815314t2.pdf · WABCO WABCO Fahrzeugbremsen Ein Unternehmensbereich der BESAN141.DOC 3/36 WABCO Standard GmbH WABCO Trailer ABS Information

WABCO WABCOFahrzeugbremsenEin Unternehmensbereich der

BESAN141.DOC 1/36 WABCO Standard GmbH

WABCO Trailer ABS Information Document 06.12.99

Directive 98/12/EC

Annex XIV

Alternative Test Procedure for Trailer Anti-Lock Braking Systems

Information Document

for

Vario Compact Trailer ABS




Contents:

2.1.1 GENERAL 3

2.1.1.1 Name of manufacturer 3

2.1.1.2 System name 3

2.1.1.3 System variations 3

2.1.1.4 System configurations 3

2.1.1.5 Explanation of the basic function and philosophy of the system 3

2.1.2 APPLICATIONS 4

2.1.2.1 List of trailer types and ABS configurations 4

2.1.2.2. Schematic diagrams of the system configurations 4

2.1.2.3 Relationship of tyre circumference to the resolution of the exciter 4

2.1.2.4 Tolerance on tyre circumference between one axle and another fitted with the sameexciter 5

2.1.2.5 Scope of application with respect to suspension type 5

2.1.2.6 Recommendations on differential brake input torque in relation to the ABSconfiguration and trailer bogie 5

2.1.2.7 Test data of energy consumption 5

2.1.2.8 Additional information to the application of the anti-lock braking system 6

2.1.3 COMPONENT DESCRIPTION 7

2.1.3.1 Sensors 7

2.1.3.2 Controllers 7

2.1.3.3 Modulators 8

2.1.3.4 Electrical Equipment 9

2.1.3.5 Pneumatic circuits 10

2.1.4 ELECTROMAGNETIC COMPATIBILTY (EMC) 11

2.1.5 APPENDICES 11

Appendix 1: configurations of sensors and modulators for different trailer types 12

Appendix 2: relationship between tyre circumference and number of polewheel teeth 15

Appendix 3: modulator types 16

Appendix 4: VCS wiring diagram 17

Appendix 5: brake diagrams 18

Appendix 6: EMC approval report 34

Appendix 7: Approved Suspension Types 36




2.1.1 General

2.1.1.1 Name of manufacturer

WABCOFahrzeugbremsenAm Lindener Hafen 21D-30453 HannoverGermany

2.1.1.2 System name

Vario Compact Trailer ABS

2.1.1.3 System variations

The Vario Compact ABS ECU and modulator components can be mountedseperately on the vehicle frame. Alternatively integrated units are available, whereECU and modulator are combined to one compact unit.

Standard power supply is 24 Volts, but also 12 Volt versions are available.

2.1.1.4 System configurations

2S/2M: two sensors and two modulators

4S/2M: four sensors and two modulators

4S/3M: four sensors and three modulators

2.1.1.5 Explanation of the basic function and philosophy of the system

The Vario Compact ABS is installed as an ”add-on”-system in line with the servicebraking system.

The sensors fitted to the wheels are inductive wheel speed sensors generating anelectrical signal proportional to its wheel’s speed. The electronic control unitprocesses these signals into logical quantities for controlling the braking pressurevia the modulators according to load and road conditions. In case of a lockingtendency the brake cylinder pressure of the corresponding wheel will be released,kept constant during expected or measured wheel re-acceleration and is increasedstepwise after re-acceleration to start the ABS-cycle again if the brakeforce is stilltoo high for actual friction.

The electrical system monitors itself. In the event of a fault, any parts found to bedefective are selectively switched off, and the warning facility is actuated. Even in




the event of the whole system is being switched off, the function of the brakingsystem covered by the ABS is maintained (although without ABS control).

Correct electrical/electronic functioning of the ABS is indicated by a warning facilityin the driver’s cab of the towing vehicle, or a warning light on the headboard of thetrailer.

2.1.2 Applications

2.1.2.1 List of trailer types and ABS configurations

The Vario Compact ABS applies semitrailers, central axle trailers or drawbar trailersof categorie O3 and O4 with air braking systems according to 98/12/EG.

No. ofaxles

2S/2M 4S/2M 4S/3M

1 x - -

semi-trailer 2 x x x3 x x x

1 x - -

central-axle trailer 2 x x x3 x x x

full trailer 2 - - x3 - - x

The running gear can have mechanical or air suspension. Depending on thespecific requirements of the respective trailer special equipment may be fittedupstream of the modulator, e. g. automatic load sensing valve, reducing, pressurelimiting or adapting valves.

The braking system may be equipped with drum brakes or disc brakes.

For sample diagrams see 2.1.3.5.

2.1.2.2. Schematic diagrams of the system configurations

Appendix 1 shows possible configurations of sensors and modulators for thedifferent trailers defined in item 2.1.2.1.

2.1.2.3 Relationship of tyre circumference to the resolution of the exciter




The sensor frequency must be in the range of 7,05 Hz/(km/h) to 10,14 Hz/(km/h).When sensing an exciter with 100 teeth, this frequency range corresponds to awheel circumference of 2 740 mm to 3 940 mm. This represents a tolerance rangeof - 20 % ... + 15 % using a standard circumference of 3 425 mm. For other tyredimensions out of this range corresponding exciters must be used as shown inappendix 2.

2.1.2.4 Tolerance on tyre circumference between one axle and another fitted with the same exciter

The sum of rolling circumference tolerances for the permissible tyre combinationsfor the vehicle must not exceed a value of 6,5 %. Otherwise the number of teeth onthe pole wheels must be adjusted to the respective tyre circumferences as shown inappendix 2.

2.1.2.5 Scope of application with respect to suspension type

The Vario Compact ABS is applicable to trailers with mechanical or air suspension.Appendix 7 defines specific suspension types by manufacturer for use.

2.1.2.6 Recommendations on differential brake input torque in relation to the ABS configuration and trailer bogie

For multiple-axle applications an almost identical utilization of friction of these axlesis required. If all of the wheels are not fitted with sensors, the axle(s) which usuallylock(s) first must be equipped with sensors.

Multiple-axle applications having only static axle load proportioning must beequipped in that way that the wheels of all axles reach their locking pointsimultaniously and that one wheel directly controlled- does not control more than two other wheels

or- in the case of central axle trailers does not indirectly control more than one

wheel or one axle

2.1.2.7 Test data of energy consumption

The energy consumption has been tested according to paragraph 6.1 of annex 10of 98/12/EG and annex 13 of ECE R 13, series 09, respectively. To determine theworst case a variation of axle load has been made. Within a range of ±10.000 N ofthe worst case the energy consumption for different ABS configurations have beendetermined.

During all energy consumption tests the load sensing valve was in a fully ladenposition. Automatic slack adjusters (if installed) were out of operation, unless thevehicle with disc brakes (due to the design of this brake type).




The following table represents the data of the energy consumption tests. It showsthe supply pressure after ABS control of 15 sec and five additional applications. Theresults are different for O3- and O4-vehicles.

Energy Consumption

0

20

40

60

80

100

120

1,5 2,0 2,5 3,0 3,5 4,0 4,5

Axle load in kg*1000

O3-vehicles O4-vehicles

2.1.2.8 Additional information to the application of the anti-lock braking system

Each electronic control unit has a standard parameter setting depending on theWABCO part number and identification. Any defect can therefore be displayed forany specific system. The connection of an ECU, with its parameters setcorrespondingly, to a system arrangement is indicated by the warning facilitystaying on, and a specific error message.




2.1.3 Component description

2.1.3.1 Sensors

Inductive wheel speed sensors are mounted opposite to a toothed wheel andgenerate an AC voltage with variable frequency depending on the wheel speed.

The sensors transmit the information from the rotating toothed wheels to theECU. Based on this information the ECU calculates the wheel and vehiclespeeds. Special care must be taken to ensure accurate speed information.

Identification:

Wheel speed sensors: WABCO part number 441 032 ... 0

Sensors are mounted in clamp bushings, WABCO part number 899 760 510 4 or899 759 815 4

2.1.3.2 Controllers

The Electronic Control Unit (ECU) controls and supervises the connectedcomponents. Main features are:

• ABS control in case of locking tendency of the wheels• fault detection• diagnostic communication The ECU is designed in a microprocessor-controlled digital technology with systemrecognition and adjustable parameters. Main inputs and outputs are: • power supply accoding to ISO 7638• alternative power supply according ISO 1185 or ISO 3731• up to four inputs for wheel speed signals• up to three outputs for activating the modulators

Failure modes:

The electrical system monitors itself. In the event of a fault, any parts found to bedefective (ECU, sensors, modulator(s)) are selectively switched off, and the warningfacility is actuated. Even in the event of the whole system being switched off thefunction of the braking system covered by ABS is maintained (although with ABScontrol).

Correct electrical/electronic function of the ABS is indicated by a warning facility inthe drivers cab in the towing vehicle (via pin 5 of the electrical connector conformingto ISO 7638) or a warning light on the headboard of the trailer.

Identification:




Electronic Control Unit: WABCO part numbers 446 108 030 0 to 446 108 050 0(further versions are possible)

Additional features:• retarder control• integrated speed switch• speed output• diagnostic interface according to ISO 9141• internal and external blinkcode• automatic recognition of lift axles

2.1.3.3 Modulators The ABS modulator valve serves the purpose of holding the pressure or venting thebrake chambers, this is being done independently of the pressure that is transmittedby the brake valve of the trailer. Several types of modulators can be used (pleasealso refer to appendix 3): ABS Relay Valve Electrically driven relay valves -both single or horizontally opposed relay valves- withthe functions of: • holding pressure (solenoid EV activated)• reducing pressure (solenoid AV activated)• increasing pressure (no solenoid active) During a brake application without ABS active due to high friction surface, thedevice operates as a relay valve; pressure that is put in the relay valve, is notinfluenced by the valve. WABCO part numbers: 472 195 020 0 to 472 195 033 0 (further versions are possible) For limitations of application regarding volume of brake chamber etc. see theWABCO product specification of the valve. ABS Solenoid Control Valve Electrically controlled modulators with the functions of: • holding pressure (solenoid EV activated)• reducing pressure (solenoid EV and AV activated)• increasing pressure (no solenoid active)




During a brake application without ABS active due to high friction surface, thedevice has no function; pressure that is put in the valve, is not influenced bythe valve. WABCO part numbers: 472 195 002 0 to 472 195 019 0 472 195 050 0 to 472 195 054 0 (further versions are possible) For limitations of application regarding volume of brake chamber etc. see theWABCO product specification of the valve.

2.1.3.4 Electrical Equipment The circuit diagram in appendix 4 shows the connection of all external components(power supply, sensors, modulators). All components are connected via externalconnectors, which are moulded and coded to avoid mismatching. All cables andconnectors fullfil GGVS resp. ADR requirements. Powering methods • standard powering of the ECU and modulators via power connector according to

ISO 7638-1 (24V) or ISO 7638-2 (12V)• alternative powering is possible according to:

- ISO 1185 (24N, port 1 and 4 of the 7-pole plug-in connection) or - ISO 3731 (24S, port 2 and 6 of the 7-pole plug-in connection)

Warning lamp sequence The ECU can perform two different warning lamp sequences. The sequence can bechanged by parameter setting. 1st Option: When the vehicle is stationary:• warning facility comes on after the power supply is switched on• if no current error is detected, the warning facility is switched off after app. 3

seconds.• if during prior driving a sensor or air gap fault was detected, the warning facility is

not turned off until v ≥ 7 k.p.h. (provided there is no current error present) When the vehicle is moving at v ≥ 7 k.p.h.:• Warning facility comes on or stays on if an error is detected 2nd Option: When the vehicle is stationary:• warning facility comes on after the power supply is switched on




• if no current error is detected the warning facility will go off after app. 3 secondsand come on again after further 2 seconds. The warning facility is switched offafter v ≥ 7 k.p.h.

• if, however, a current error has been detected, e.g. of the sensor/air gap fault,the warning facility will stay on permanently after power supply has beenswitched on.

2.1.3.5 Pneumatic circuits

Sample brake diagrams for different trailers with standard air brakes arerepresented in appendix 5 (page 1 to 16):

Page 1: 1-axle central axle trailer with 2S/2MPage 2: 2-axle central axle trailer with 2S/2MPage 3: 2-axle central axle trailer with 2S/2M (diagonal axle regulation, DAR)Page 4: 2-axle central axle trailer with 2S/2M or 4S/2MPage 5: 2-axle central axle trailer with 4S/3MPage 6: 3-axle central axle trailer with 2S/2MPage 7: 3-axle central axle trailer with 4S/2MPage 8: 3-axle central axle trailer with 4S/3MPage 9: 1-axle semi-trailer with 2S/2MPage 10: 2-axle semi-trailer with 2S/2M or 4S/2MPage 11: 2-axle semi-trailer with 4S/3MPage 12: 3-axle semi-trailer with 2S/2MPage 13: 3-axle semi-trailer with 4S/2MPage 14: 3-axle semi-trailer with 4S/3MPage 15: 2-axle trailer with 4S/3MPage 16: 3-axle trailer with 4S/3M

Limitation on pipe/tube size and associated lengths:

The length of the hoses between modulator valve and brake chambersshould be as short as possible. If the cross section of the hose from themodulator valve to the brake cylinder is 9 mm the maximum length is 2.5 m.If the cross section of the hose from the modulator valve to the brake cylinderis 11 mm the maximum length is 3.0 m. All brake chambers actuated by themodulator valve should be connected with the same pipe length and crosssection to the device.

In any case the gradient of pressure decrease in the brake chamber shouldbe 20 bar/s at least (between 5 and 2 bar) to assure sufficient performance.

The size of brake chambers should not exceed 3 x type 30 per relaymodulator resp. 2 x type 30 per solenoid control valve. The cross section forthe air supply hose to the relay modulator valve (fitted to port 1) should bechoosen as wide as possible; recommended is a minimum of 9 mm.




2.1.4 Electromagnetic Compatibilty (EMC)

The Vario Compact ECU has been certified according to 72/245/EEC (last amendedby Directive 95/54/EC).

The type approval number is e1*72/245*95/54*1058.

The EMC approval report is enclosed in appendix 6.

Further EMC tests have been carried out to verify sufficient immunity levelequivalent to 100 V/m. Emission tests have been made to check out that there is nodisturbance in radio frequency communication on vehicles.

2.1.5 Appendices


BESAN141.DOC WABCO Standard GmbH


Appendix 1: configurations of sensors and modulators for different trailer types(page 1/3)




Appendix 1 (page 2/3)








Appendix 2: relationship between tyre circumference and number of polewheel teeth(page 1/1)




Appendix 3: modulator types(page 1/1)




Appendix 4: VCS wiring diagram(page 1/1)

Appendix 5: brake diagrams(page 1/16) page 18/36

Appendix 5 (page 2/16) page 19/36


















Appendix 6: EMC approval report(page 1/2)








Appendix 7: Approved Suspension Types

Manufacturer Model TypeAcerbi AV Air suspension, balanced

Bartoletti Bartoletti Air suspension, balancedBartoletti Mechanical

BPW SLU. SLO, SLM, VA Air suspension, balancedVB, GW, BW, VG, VB Mechanical

Cardi PR, PR Air suspension, balancedMR Mechanical

Cometto SP1, SP2 Air suspension, balancedMA3 + G1 Mechanical

Gigant / SAE LG, TLG, LR, TLR, NLR,TO Air suspension, balancedLK Mechanical

Granning PTS, PTL Air suspension, balanced

Hendrikson HTE, HT 250 Air suspension, balancedHST Mechanical

Meritor Flexair, Indair Air suspension, balancedSMT Mechanical

Piazenza U2, N2, P1, R2, S2,V1, V2, Air suspension, balancedR2, N2, S2 Mechanical

Rolfo 7T, 10T, 16T Air suspension, balanced

SAF Intraax, Intradisk, Intradiskplus, IWST, Modul

Air suspension, balanced

SMB NA, SA, ZA Air suspension, balancedFA Mechanical

Weweler Euro, Heavy Duty, Mega Lite:Specials; Ultra Lite


Viberti AV Air suspension, balanced

Zorzi B4P, R4P, R6P, R10P, S6P,S10P, S12P


S6M, S10M, R10M Mechanical

Documents

WABCOinform.wabco-auto.com/intl/pdf/815/000/314/815314t2.pdf · WABCO WABCO Fahrzeugbremsen Ein Unternehmensbereich der BESAN141.DOC 3/36 WABCO Standard GmbH WABCO Trailer ABS Information