Document ID: chunk:federal_register_of_legislation:F2021C01192:body:0:p34
Version: federal_register_of_legislation:F2021C01192
Segment Type: other
Provision Reference: 
Character Range: 91603–94475

performance of the combination shall not be less
than 5.4 m/s2 in both the laden and unladen conditions.
 The combination performance shall be verified by calculations referring to the maximum braking performance actually achieved by the motor vehicle alone (laden) during the Type-0 test with the engine disconnected, using the following formula (no practical tests with a coupled unbraked trailer are required):

  Where:
                     dM+R = calculated mean fully developed deceleration of the motor vehicle when coupled to an unbraked trailer, in m/s2
                     dM = maximum mean fully developed deceleration of the motor vehicle alone achieved during the Type-0 test with engine disconnected, in m/s2
                     PM = mass of the motor vehicle (laden)
                     PR = maximum mass of an unbraked trailer which may be coupled, as declared by the motor vehicle manufacturer.
2.2.  Secondary braking system
2.2.1.  The performance of the secondary braking system shall be tested by the Type-0 test with the engine disconnected from an initial vehicle speed of 100 km/h and a force applied to the service brake control not less than 6.5 daN and not exceeding 50 daN.
2.2.2.  The secondary braking system shall give a stopping distance not exceeding the following value:
0.1 v + 0.0158 v2 (m)
 and a mean fully developed deceleration not less than 2.44 m/s2 (corresponding to the second term of the above formula).
2.2.3.  The secondary braking effectiveness test shall be conducted by simulating the actual failure conditions in the service braking system.
2.2.4. For vehicles employing electric regenerative braking systems, the braking performance shall additionally be checked under the two following failure conditions:
2.2.4.1.  For a total failure of the electric component of the service braking output.
2.2.4.2. In the case where the failure condition causes the electric component to deliver its maximum braking force.
2.3.  Parking braking system
2.3.1.  The parking braking system shall be capable of holding the laden vehicle stationary on a 20 per cent up or down gradient.
2.3.2.  On vehicles to which the coupling of a trailer is authorized, the parking braking system of the motor vehicle shall be capable of holding the combination of vehicles stationary on a 12 per cent up or down gradient.
2.3.3.  If the control device is manual, the force applied to it shall not exceed 40 daN.
2.3.4.  If it is a foot control device, the force exerted on the control shall not exceed 50 daN.
2.3.5.  A parking braking system which has to be actuated several times before it attains the prescribed performance is admissible.
2.3.6.  To check compliance with the requirement specified in paragraph 5.2.2.4. of this Regulation, a Type-0 test shall be carried out, with the engine disconnected, at an initial test speed of 30 km/h.