Document ID: chunk:federal_register_of_legislation:F2023C00154:reg:1:p8
Version: federal_register_of_legislation:F2023C00154
Segment Type: reg
Provision Reference: reg 1 (pt 8/15)
Character Range: 116766–119391

considered as acceptable if ∆r does not exceed 3.0 mrad.
     If this value exceeds 3.0 mrad but is not more than 4.0 mrad, the second front fog lamp of sample A shall be subjected to the test after which the mean of the absolute values recorded in both samples shall not exceed 3.0 mrad.
     However, if this value of 3.0 mrad on sample A is not complied with, the two front fog lamps of sample B shall be subjected to the same procedure and the value of ∆r for each of them shall not exceed 3.0 mrad.
Figure 1
Annex 9

Definition and sharpness of the cut-off line and aiming procedure by means of this cut-off line for Class F3 front fog lamps
     1. General
      The luminous intensity distribution of the front fog lamp shall incorporate a cut-off line that enables the front fog lamp to be adjusted correctly for the photometric measurements and for the aiming on the vehicle. The characteristics of the cut-off line shall comply with the requirements set out in paragraphs 2. to 4. below.
     2. Shape of the cut-off line
     For visual adjustment of the front fog beam the cut-off line shall provide a horizontal line for vertical adjustment of the front fog lamp extending to 4° either side of the v‑v line (see Figure 1).
     3. Adjustment of the front fog lamp
     3.1. Horizontal adjustment
     The cut-off line shall be so positioned that the projected beam pattern appears approximately symmetrical to the v‑v line. When the front fog lamp is designed for use in pairs or has otherwise an asymmetric beam pattern, it shall be horizontally aligned according to the specification of the applicant, or otherwise in such a way that the cut-off line appears symmetrical to the v‑v line.
     3.2. Vertical adjustment
     After horizontal adjustment of the front fog beam according to paragraph 3.1. above, the vertical adjustment shall be performed in such a way that the cut-off line is moved upwards from the lower position until it is situated on the v‑v line at 1° below the h‑h line. If the horizontal part is not straight but slightly curved or inclined, the cut-off line shall not exceed the vertical range formed by two horizontal lines which are situated between 3° left and right of the v‑v line at 0.2° above and below the nominal position of the cut-off (see Figure 1).
     3.2.1. When the vertical positions of three attempts to adjust the cut-off differ by more than 0.2°, the horizontal part of the cut-off line is assumed not to provide sufficient linearity or sharpness for performing visual adjustment. In this case the quality of cut-off shall be tested instrumentally for compliance with