BS ISO 14793:2011 pdf free download – Road vehicles一Heavy commercial vehicles and buses Lateral transient response test methods.
8.4 Test vehicle
8.4.1 Generaldata
Appropriate general data on the test vehicle or vehicle unit shall be presented in the test report in accordance
with Annex A.
8.4.2 Tyres
For the standard test conditions, new tyres shall be fitted on the test vehicle according to the vehicle manufacturers specifications. They shall have a tread depth of at least 90 % of the original value in the principal grooves within 0,75 of the tread breadth (in accordance with specifications for tread-wear indicators given in ECE Regulation No. 30), shall have been stored in accordance with the manufacturer’s recommendation and shall not have been manufactured more than two years prior to the test. The date of manufacture shall be noted in the test report (see Annex A).
NOTE The tread breadth is the width of that part of the tread which, with the tyre correctly inflated, is in contact with the road in normal straight-line driving.
If not otherwise specified by the tyre manufacturer, the tyres sha’l be run in for at least 150 km on the test vehicle or an equivalent vehicle without excessively harsh use such as severe braking, acceleration, cornering or hitting the kerb, After running in, the tyres shall be maintained at the same position on the vehicle throughout the tests.
Tyres shall be inflated to the pressure specified by the vehicle manufacturer for the test vehicle configuration. The tolerance for setting the cold inflation pressure is ± 2 %.
Inflation pressure and tread depth before tyre warm-up and after completion of the test shall be recorded in the test report (see Annex A).
The tests may also be performed with tyres in any state of wear as well as with retreaded or regrooved tyres. The details shall be recorded in the test report (see Annex A). As tread depth or uneven tread wear can have a significant influence on test results, these should be taken into account when making comparisons between vehicles or between tyres.
8.4.3 Other operating components
For the standard test conditions, any operating component likely to influence the results of a test (e.g. shock absorbers, springs and other suspension components and suspension geometry) shall be as specified by the manufacturer. Any deviations from the manufacturers specification shall be recorded in the test report (see Annex A).
Levelling systems of the chassis and cabin suspension which affect the response behaviour inappropriately should be disabled during steady-state and step-input tests.
8.4.4 Vehicle loading conditions
8.4.4.1 General
The maximum design total mass (Code: ISO-M07) and the maximum design axle load (Code: lSO-M12), in accordance with ISO 1176:1990, 4.7 and 4.12, shall not be exceeded.
The total weight and the centre-of-gravity position (longitudinal, lateral and vertical) can be expected to influence all test results. Moments of inertia can be expected to influence transient test results. For all tests, the total mass and the centre-of-gravity position in three dimensions should be reported for each vehicle unit, and for transient tests, the moment of inertia in yaw should also be reported. Moments of inertia in pitch and roll should be reported if available.