Document ID: chunk:federal_register_of_legislation:F2021C01192:body:0:p43
Version: federal_register_of_legislation:F2021C01192
Segment Type: other
Provision Reference: 
Character Range: 114658–117479

this Regulation, if it provides performance equal to that prescribed by this annex.
2.   Definitions
2.1.  An "anti-lock system" is a part of a service braking system which automatically controls the degree of slip, in the direction of rotation of the wheel(s), on one or more wheels of the vehicle during braking.
2.2.          "Sensor" means a component designed to identify and transmit to the controller the conditions of rotation of the wheel(s) or the dynamic conditions of the vehicle.
2.3.          "Controller" means a component designed to evaluate the data transmitted by the sensor(s) and to transmit a signal to the modulator.
2.4.     "Modulator" means a component designed to vary the braking force(s) in accordance with the signal received from the controller.
2.5.     "Directly controlled wheel" means a wheel whose braking force is modulated according to data provided at least by its own sensor.[15]
2.6.     "Indirectly controlled wheel" means a wheel whose braking force is modulated according to data provided by the sensor(s) of other wheel(s).1
2.7.     "Full cycling" means that the anti-lock system is repeatedly modulating the brake force to prevent the directly controlled wheels from locking. Brake applications where modulation only occurs once during the stop shall not be considered to meet this definition.
3.  Types of anti-lock systems
3.1.  A vehicle is deemed to be equipped with an anti-lock system within the meaning of paragraph 1. of Annex 5 to this Regulation, if one of the following systems is fitted:
3.1.1.  Category 1 anti-lock system
  A vehicle equipped with a category 1 anti-lock system shall meet all the requirements of this annex.
3.1.2.  Category 2 anti-lock system
  A vehicle equipped with a category 2 anti-lock system shall meet all the requirements of this annex, except those of paragraph 5.3.5. below.
3.1.3.  Category 3 anti-lock system
  A vehicle equipped with a category 3 anti-lock system shall meet all the requirements of this annex, except those of paragraphs 5.3.4. and 5.3.5. below. On such vehicles, any individual axle which does not include at least one directly controlled wheel shall fulfil the conditions of adhesion utilization and the wheel-locking sequence of Annex 5 to this Regulation, instead of the adhesion utilization requirements prescribed in paragraph 5.2. of this annex. However, if the relative positions of the adhesion utilization curves do not meet the requirements of paragraph 3.1. of Annex 5 to this Regulation, a check shall be made to ensure that the wheels on at least one of the rear axles do not lock before those of the front axle or axles under the conditions prescribed in paragraph 3.1. of Annex 5 to this Regulation, with regard to the braking rate and the load respectively. These requirements may be checked on