ISO 3450-2011 pdf free download.Earth-moving machinery — Wheeled or high-speed rubber-tracked machines — Performance requirements and test procedures for brake systems.
4.1.2 No brake system (including hydrostatic systems) shall contain a disconnecting device such as a clutchor shiftable gear-box which allows disabling of the brake, except for systems in accordance with a) and/or b), asfollows:
a)any device designed to disconnect the service or secondary brake power source for cold weather starting
shall require application of the parking brake before disconnection can take place;
b) a parking brake disconnect (release) designed to allow movement of disabled machines shall be located
outside the operator’s station unless it can be reapplied immediately.
4.1.3 All machines shall have service brakes of an equal nominal capacity rating applicable to each of thewheels (or equivalent) of at least one axle. Dumpers and self-propelled scrapers with semi-trailed unit(s) shallhave service brakes applicable to at least one axle of the towing machine and one axle of each semi-trailed unit.
4.1.4 For rollers, the service and secondary brakes shall apply to all power-driven drums and wheels.Eachdrum of a split drum shall have the same nominal brake torque.The brake of a single-drum roller and a combinedroller shall apply to all wheels and to the drum.
4.1.5 lf the parking brake is intended to stop creep movement, the parking brake system shall permit actuationof the parking brake during travel.
4.2Common components
Service, secondary and parking brake systems can share common components. Where common componentsare used, the machine’s braking performance shall meet the requirements for secondary brake systems givenin 4.5 and 4.7, as applicable. lf there is a failure in any single component within the brake system —except fortyres, drum or track — braking performance shall be in accordance with Table 3.
Acceptable performance is achieved for common brake control failure as follows. if there is a failture with acommon brake control (lever, pedal, etc.) used to actuate the combined service and secondary brake systems,and there is another dynamic braking capability provided with the machine (e.g. parking brake with dynamicbraking capability), the dynamic braking capability shall stop the machine after the failure within 120 % of thestopping distance for secondary brakes (under secondary test conditions) in accordance with Table 3.Thisdynamic braking capability may be applied automatically and without modulation. An indication should be givento the operator simultaneous with, or before, application of the brake system, if applied automatically.
4.3Brake control systems
All brake system controls shall be capable of being applied by an operator from the operating position. Parkingbrake system controls shall be arranged so that, unless immediately reapplied, they cannot be released onceapplied.
Unintended brake control activation can be avoided through compliance with ISO 10968.
Brake control systems should be designed to avoid any unintended application or release of brakes duringnormal operation. This does not preclude the automatic application of a brake system due to intended designconditions that also meet the requirements of this International Standard.
The arrangement of the brake system controls should be in accordance with ISO 10968.If not, an instructionalsign shall be provided (e.g. using symbols) explaining the control arrangement. Brake pedals and hydrostaticbrake system controls are obvious and may not require machine instructions.
A brake control system shall prevent or minimize any uncontrolled braking performance (random brakeapplications, releases or sporadic braking performance,etc.) during normal operation (start, stop or normaltravel operation of the machine, etc.).
Electric, electronic and electronic machine control systems (MCS) for service,secondary or parking brakesshall comply with ISO 15998.ISO 3450 pdf download.