BRITISH STANDARD AUTOMOBILE SERIES BS AU 234 1989 ISO 8856 1988 Methods of test and general requirements for road vehicle starter motors BS AU 234 1989 This British Standard, having been prepared unde[.]
BRITISH STANDARD AUTOMOBILE SERIES Methods of test and general requirements for road vehicle starter motors BS AU 234: 1989 ISO 8856:1988 BS AU 234:1989 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Automobile Standards Policy Committee (AUE/- ) to Technical Committee AUE/1 6, upon which the following bodies were represented: Association of Trailer Manufacturers British Cable Makers’ Confederation Department of Transport (Highways) Department of Transport (Transport and Road Research Laboratory) Department of Trade and Industry Institution of Electronic and Radio Engineers National Caravan Council Ltd Society of Motor Manufacturers and Traders Ltd This British Standard, having been prepared under the direction of the Automobile Standards Policy Committee, was published under the authority of the Board of BSI and comes into effect on Amendments issued since publication 29 September 989 © BSI 2- 999 The following BSI references relate to the work on this standard: Committee reference AUE/1 Draft for comment 86/70623 DC ISBN 580 17432 Amd No Date of issue Comments BS AU 234:1989 Contents Page Committees responsib le Inside front cover National foreword Scope and field of application D efinitions Test conditions Test benches Procedure Presentation of results Figure — Voltage/current characteristic of starter motor power supply © BSI - 999 ii Figure — Type test b ench Figure — Type test b ench Figure — Presentation of results Tab le — Measurement accuracy Tab le — Voltage/current characteristic of starter motor power supply i BS AU : 989 National fore word This British Standard has been prepared under the direction of the Automobile Road vehicles — Starter motors — Test methods and general requirements”, published Standards Policy Committee and is identical with ISO 8856: 988 “ by the International Organization for Standardization (ISO) A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application C omp liance with a British S tand ard d oe s no t of itse lf confe r immunity from le gal ob ligatio ns S ummary of p age s This document comprises a front cover, an inside front cover, pages i and ii, pages to and a back cover This standard has been updated (see copyright date) and may have had amendments incorporated This will be indicated in the amendment table on the inside front cover ii © BSI 2- 999 BS AU : 989 S cop e and fie ld of ap p lication b) one pair of values U, I and the internal resistance of the starter motor power supply; c) one pair of values U, I and the slope mV/A This International Standard lays down test methods and general requirements for the determination of the electrical characteristic data of starter motors of the terminal voltage divided by the starter It applies to d.c starter motors mounted on internal value motor current draw with the armature shaft locked combustion engines for road vehicles (no rotation) 2.5 inte rnal re sistance of the starte r moto r D e finitions For the purposes of this International Standard, the following definitions apply 2.1 nominal p o we r as defined by the starter motor manufacturer; it corresponds to the maximum power output when tested in accordance with this International Standard 2.2 p o we r outp ut power derived from measurements of torque and speed 2.3 p o we r sup p ly battery or simulator which delivers a voltage characteristic as defined in this International Standard 2.4 voltage /curre nt characte ristic of p ow e r sup p ly in the voltage/current diagram, the straight line directed downwards The voltage values are taken at the starter motor terminals NOTE The characteristic in the voltage/current diagram can be determined by: a) two pairs of values U1, I1 and U2, I2; Te st conditions Te mp e rature and time Tests shall be carried out at an ambient temperature of 23 ± °C 3.1.1 Test method A Time for single point measurements: s Starter motor at ambient temperature of 23 ± °C 3.1.2 Test method B Total test time: 10 s a) Starter motor at ambient temperature of 23 ± °C, or b) to avoid a need for temperature correction, the starter motor preconditioned at 20 ± 0,5 °C Accuracy o f me asure me nt The overall capability of the test equipment shall enable the parameters to be measured within the tolerances shown in Table Tab le — Me asure me nt accuracy Accu racy Parame te r Current Voltage Rotational frequency Torque 1 ± ± % ± ± Vo ltage /curre nt characte ristic of starte r moto r p ow e r sup p ly The selection of voltage/current characteristic shall be taken from Table 2, shall not exceed the recommendations of the starter motor manufacturer, and shall meet the battery discharge capability as agreed between the starter motor manufacturer and the vehicle manufacturer Figure — Vo ltage /curre nt characte ristic of starte r mo tor p o we r sup p ly © BSI 12-1999 BS AU : 989 Tab le — Voltage /curre nt characte ristic of starte r mo tor p o we r sup p ly The test bench in Figure (type 2) permits direct starter motor measurement at the armature shaft Pai r o f value s No mi nal U vo ltage I V V A U V I Typ e I a b A A The starter motor shall be coupled to the test device coaxially through a suitable coupling The starter motor end bracket may be replaced by a special 250 300 300 bracket with bearing to permit coupling to the starter motor shaft 350 400 450 Procedure 500 Te st me tho ds 550 12 12 600 600 800 900 900 000 200 200 500 500 700 600 600 800 900 12 900 000 200 500 500 000 400 b Run the starter motor at various discrete torque loads and record the torque, current, voltage and rotational frequency at each of these discrete points International Standard (see Figure 4) After each point, the starter motor shall be cooled down to ambient temperature (see 5.1.2 200 700 a Method A — Discrete point method which shall be plotted in accordance with this 500 24 5.1.1 Enough points shall be recorded to develop a curve 000 24 One of the following two test methods, A or B, may be applied to measure performance data Extended list Short list Numb e r of te sts In order to ensure uniform functioning of the new starter motors under test, the test shall be repeated three times: the performance recorded shall be the last of these Method B — Continuous mode method Operate the starter motor in a continuous mode, increase the torque load (until the stall point, if required) while torque, current, voltage and rotational frequency are automatically recorded Me asure me nt corre ctio n Correction to reference temperature of 20 °C 5.2.1 In the case where the starter motor temperature is not 20 ± 0, °C [see 3.1 and 3.1 a)] , a correction of rotational frequency and torque may be necessary (depending upon the type of field system used) 5.2.2 Te st b enche s 3.1.1) Correction of torque 5.2.2.1 Correction of torque with inertia The following two types of test bench, as shown in Torque measurement is recorded as either a frame Figure and Figure 3, can be applied reaction or as taken at the torque loading point NOTE In the second case the following corrections apply Geared and non- geared test benches produce different apparent power and this should be taken into consideration, particularly when testing small power starter motors Typ e The test bench in Figure (type ) allows performance measurements to be established by engaging the pinion with a ring- gear The backlash a) For a type test bench Correction shall be made for pinion and ring- gear efficiency (This type of test bench produces smaller torques than a type test bench ) between the pinion and the ring- gear teeth shall be in accordance with the starter motor manufacturer’s recommendations © BSI 2- 999 BS AU 234:1989 b) For test method B Use the following correction for torque, M, for armature deceleration: M= M measured – M (1 ) correction J correction = ; × %n × ( J %t 30 × br + J is the moment of inertia of the measuring device expressed in kilogram square metres; J a M is the time difference between two braking points expressed in seconds; br where is the moment of inertia of armature and other revolving parts expressed in kilogram a ) square metres For starter motors with built- in reduction gear, the in which %n %t moment of inertia of the armature shall be referred is the rotational frequency difference to the pinion shaft between two braking points expressed in minutes to the power minus one; Figure — Type test bench Figure — Type test bench © BSI 2- 999 BS AU : 989 For temperature change t1 to t2, in degrees Celsius, the starter motor’s internal resistance changes from R1 to R2 R2 is given by the formula R2 = [1 + µ (t2 – t1 )] ì R1 (6) where is the temperature coefficient of resistance at temperature t2 for the starter motor winding material 2) In the case of permanent magnetic field starter motors, the magnetic flux Ì changes with the temperature t The rotational frequency change n1 to n2 is then calculated using the formula E n = E2 – ¶ t1 – t n (7) The power characteristic, P, in kilowatts, of the starter motor may be determined by For ¶, see M n To change the frequency characteristic of a P = 549,3 (3) performance curve as in Figure 4, the following data are taken at suitable steps of current: where a) starter motor rotational frequency, n; M is the torque, in newton metres; b) terminal voltage, U; n is the rotational frequency which is the c) starter motor resistance, R number of revolutions divided by time, in minutes to the power minus one The rotational frequency is corrected using equation (7) at each selected value of current and thus a new frequency characteristic curve is The rotational frequency, n, is given by the established formula For changes in applied voltage, the value U in n = k -EÌ (4) equation (5) is affected, and the rotational frequency calculated using equation (7) The power output characteristic is calculated as in where k is a constant depending on the starter motor size; Performance characteristics shall be presented in E is the back-electromotive force; accordance with Figure Where necessary, the Ì is the magnetic flux available in the starter measured parameters shall be corrected to the motor field reference temperature of 20 °C (see ) and the Frequency change is generally calculated by test bench employed shall be specified comparing the back-electromotive forces using the If a calculated value of µ is used, the value should be equation recorded E = U– I× R (5) If so desired, the starter motor performance may be reproduced as a rotational frequency/torque where characteristic E is the back-electromotive force; U is the applied voltage; I is the starter motor current; R is the internal resistance of the starter motor Correction of torque with temperature If the temperature changes from t1 to t2, the torque shall be corrected in M1 as corrected in accordance with the following formula to give torque M2: M2 = M1 [1 – ¶ (t1 – t2)] (2) where ¶ is the magnetic induction coefficient of the permanent magnetic field as a function of temperature 1) In the case of a wound field starter motor, ¶ = 5.2.2.2 5.4.3 5.2.2.1 5.4.4 D e te rminatio n of starte r moto r outp ut characte ristic × ( ) × 5.2.2.2 × 4.5 4.6 D e te rmination of ro tational fre que ncy 5.4.1 4.7 5.3 Pre se ntation of re sults 5.2.1 5.4.2 1) The value of ¶ may vary between – × 10 –3 °C –1 and – 2,3 × 10 –3 °C –1 2) The value of µ for copper (100 %) as in the International Annealed Copper Standard (IACS), is equal to 3,93 × 10 –3 °C –1 at 20 °C For starter motors constructed with composite copper/aluminium windings, it will be necessary to calculate a value for µ © BSI 12-1999 BS AU 234:1989 Figure — Presentation of results © BSI - 999 BS AU 234: 1989 ISO 8856:1988 BSI — British Standards Institution BS I is the indep endent national b ody res p ons ib le for p rep aring Britis h S tandards It p res ents the UK view on s tandards in E urop e and at the international level It is incorp orated b y Royal C harter Revisions Britis h S tandards are up dated b y amendment or revis ion Us ers of Britis h S tandards should make s ure that they p oss es s the latest amendments or editions It is the constant aim of BS I to imp rove the quality of our p roducts and services We would b e grateful if anyone finding an inaccuracy or amb iguity while us ing this Britis h S tandard would inform the S ecretary of the technical committee res p ons ib le, the identity of which can b e found on the inside front cover Tel: 02 89 96 90 00 Fax: 02 89 96 40 BS I offers memb ers an individual up dating s ervice called PLUS which ens ures that s ub s crib ers automatically receive the lates t editions of s tandards Buying standards O rders for all BS I, international and foreign s tandards p ub lications s hould b e addres s ed to C us tomer S ervices Tel: 899 00 Fax: 899 7001 In res p ons e to orders for international standards , it is BS I p olicy to sup p ly the BS I imp lementation of thos e that have b een p ub lis hed as Britis h S tandards, unless otherwis e requested Information on standards BS I p rovides a wide range of information on national, E urop ean and international standards through its Lib rary and its Technical H elp to E xp orters S ervice Various BS I electronic information s ervices are also availab le which give details on all its p roducts and s ervices C ontact the Information C entre Tel: 02 89 96 71 1 Fax: 02 89 96 048 S ub s crib ing memb ers of BS I are kep t up to date with s tandards develop ments and receive sub s tantial discounts on the p urchase p rice of s tandards For details of thes e and other b enefits contact Memb ership Adminis tration Tel: 02 89 96 70 02 Fax: 02 89 96 00 Copyright C op yright s ub s is ts in all BS I p ub lications BS I als o holds the cop yright, in the UK, of the p ub lications of the international s tandardization b odies E xcep t as p ermitted under the C op yright, D es igns and Patents Act 988 no extract may b e rep roduced, s tored in a retrieval s ystem or transmitted in any form or b y any means – electronic, p hotocop ying, recording or otherwis e – without p rior written p ermis s ion from BS I This does not p reclude the free us e, in the cours e of imp lementing the standard, of necess ary details such as s ymb ols, and size, typ e or grade designations If thes e details are to b e used for any other p urp os e than imp lementation then the p rior written p ermiss ion of BS I must b e ob tained If p ermis sion is granted, the terms may include royalty p ayments or a licensing agreement D etails and advice can b e ob tained from the C op yright Manager BS I 89 C his wick H igh Road London W4 4AL Tel: 02 89 96 70