ISO 5721-1-2013 pdf free download

ISO 5721-1-2013 pdf free download.Agricultural tractors Requirements, test procedures and acceptance criteria for the operator’s field of vision Part 1:Field of vision to the front
Tracteurs agricoles — Exigences, modes opéra toires d’essai et critères d’acceptation relatifs au champ de visibilité du conducteur — Partie 1: Champ de visibilité vers l’avant.
There shall be no more than six masking effects in the semi-circle of vision to the front and no more than two inside the sector of vision to the front defined in IS.
For the purpose of determining the masking effects in the sector of vision to the front, the masking effects due to the frame of the windscreen and to any other obstacle may be considered as a single effect, provided that the distance between the outermost points of this masking effect does not exceed 700 mm.
Outside the sector of vision to the front, masking effects exceeding 700 mm but not exceeding 1 500 mm are, however, permissible if the components causing them cannot be redesigned or relocated: on each side there may be a total of either two such masking effects, one not exceeding 700 mm and the other not exceeding 1 500 mm, or two such masking effects, neither exceeding 1 200 mm.
5.1.3 Blind spots
Blind spots caused by rear-view mirrors shall be disregarded if the design of these mirrors is such that they cannot be installed in any other way.
5.1.4 Windscreen wipers
Tractors fitted with windscreens shall be equipped with power-driven windscreen wipers and the area swept by these wipers shall ensure an unobstructed forward view corresponding to a chord of the semicircle of vision to the front at least 8 m long within the sector of vision to the front.
The rate of operation of the windscreen wipers shall have at least one setting that provides a minimum of 20 cycles per minute.
5.1.5 Equivalent requirements
The requirements of ISO 5006:2006 are considered equivalent for the purpose ofthis International Standard.
5.2 Test procedures
5.2.1 Checking of the field of vision
The tractor shall be placed on a horizontal surface as shown in Figure 2. On a horizontal support level with the reference point, there shall be mounted two point sources of light, e.g. two x 150 W, 12 Vt 65 mm apart and symmetrically located with respect to the reference point. The support shall be pivotable at its centre point about a vertical axis passing through the reference point. For the purpose of measuring the masking effects, the support shall be so aligned that the line joining the two light sources is perpendicular to the line joining the masking component and the reference point.
The silhouette (deepest shadow) overlaps projected on to the semi-circle of vision to the front by the masking component when the light sources are switched on simultaneously or alternately shall be measured in accordance with 3.4 (Fiure3.)ISO 5721-1-2013 pdf free download.