SAE J583:2020 pdf free
SAE J583:2020 pdf free.(R) Front Fog Lamp
The lamp shall be mounted on a test fixture, which simulates the vehicle mounting system and any optically significant surrounding structures (e.g., grille, fascia, etc.) in its design operating position and orientation, at a distance of at least 10 m from the photometer.
Light sources used for testing shall meet the requirements of SAE J575. For lamps requiring incandescent bulbs, accurate rated bulbs operated at their rated luminous flux based on a design voltage of 13.2 V shall be used. Alternatively, an accurate rated incandescent bulb operated at its rated luminous flux based on a design voltage of 12.8 V can be used for testing provided that the photometric candela measurements are scaled by a factor of 1.10.
The optical axis of the front fog lamp to be tested shall be centered horizontally on the photometer axis with maximum gradient positioned as determined in 5.1.6.1.1.
Conduct a vertical scan of the lamp beam pattern along the V-V line and at 2. 5 degrees right and 2.5 degrees left of the V-V line over a sufficient vertical distance to locate the maximum gradient and determine the shape of the gradient curve. The gradient Giog should be calculated using the mathematical expression Glog = log10 l(a) – log10 l(a+0.1), where is the measured candela value and a is the vertical angular position in degrees. Plot the results Glog versus a.
The lamp aim shall be adjusted until the vertical angular position at which the maximum gradient measured along the V-V line is located at 0.75 degree down for a front fog lamp designed to conform to the requirements of photometry Figure 1 of this document or 1 degree down for a front fog lamp designed to conform to the requirements of photometry Figure 2 of this document.
If the front fog lamp is combined with a headlamp such that the front fog lamp cannot be aimed separately from the headlamp, the headlamp shall be aimed correctly, and then the front fog lamp shall then be photometrically measured per SAE J575.SAE J583 pdf free download.
