Interpretation ID: 86-3.26
TYPE: INTERPRETATION-NHTSA
DATE: 05/17/86
FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA
TO: Yueh-An Chen
TITLE: FMVSS INTERPRETATION
TEXT:
Yueh-Am Chen Division Head Planning Division Yue Loong Motor Company, Ltd. P.O. Box 510 Taoyuan Taiwan 330 Republic of China
Dear Sir:
This is in reply to your letter of January 23, 1986, asking questions about features of motor vehicle headlighting systems.
Your first question is "to which regulations the headlamp assembly unit should be conformed, if this model is to be exported to U.S.A." The regulation that applies to motor vehicle headlighting assemblies is Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment. Its official citation is Title 49 Code of Federal Regulations Section 571.108. Standard No. 108 incorporates various materials of the Society of Automotive Engineers (SAE) pertaining to headlamps, such as photometric performance.
With respect to sealed beam headlamps, you have asked whether "it is necessary for us to set the aiming adjust device in front of the lamp unit, i.e. the aiming can be adjusted outside the vehicle?" The standard requires that all headlamps, whether sealed beam or not, must be capable of mechanical aim, that is to say, with an aiming device placed in front of the lamp unit without the removal of any vehicle parts. However, the actual aim adjustment device such as a screw or knob may be located anywhere.
With respect to replaceable bulb headlamps, you have asked whether there is any regulation "regarding the maximum degree of the inclination" of the lens, such as a 20 degree maximum. No, there is no regulatory limitation. However, the headlamp must comply with the minimum photometric requirements of Standard No. 108 with the lens in its design position, and it must be mechanically aimable using equipment designed to interface with the three aiming pads required to be located on the headlamp lens. The degree to which inclination may be limited is influenced by the design of mechanical aiming equipment available in the field for aim inspection and aiming. Consequently, you should contact manufacturers of such equipment to be sure that your headlamps are designed to be mechanically aimable as required by law.
You have also asked if there is any regulation regarding the necessity of putting on or off the headlamp unit outside the vehicle, i.e. do not need to open hood." No, there is no such U.S. regulation.
Finally, you have asked "If a headlamp unit can satisfy the photometric requirements of the SAP, but a small area of the lens is shaded by the other part of the vehicle" is such a configuration permissible. The answer is yes, as long as the headlamp unit can satisfy the photometric requirements as shaded by that part of the vehicle, and as long as any replacement headlamp units produced by you or others can also meet the photometric requirements in the shaded location.
Sincerely,
Erika Z. Jones Chief Counsel
January 23, 1986
NHTSA 400 Seventh St., S.W. Washington, D.C. 20590 U.S.A.
Dear Sir,
We are the largest automobile manufacturer in Taiwan, R.O.C. In order to make our newly designed model satisfy the U.S.A. regulation, we are now confronted by some troubles in the part of headlight system. If it is possible, please provide us with the following informations:
1. To which regulations the headlamp assembly unit should be conformed, if this model is to be exported to U.S.A.
2. If adopting sealed beam headlamp unit, is it necessary for us to set the aiming adjust device in front of the lamp unit, i.e., the aiming can be adjusted outside the vehicle?
3. If adopting replaceable-bulb headlamp unit, not sealed beam, is there any regulation regarding the maximum degree of the inclination of glass lense, e.g., must be less than 20o (inclination degree (A) as showed in Fig)?
4. Is there any regulation regarding the necessary of putting on or off the headlamp unit outside the vehicle, i.e., do not need to open the hood:
5. If a headlamp unit can satisfy the photometric requirements of the SAE, but a small area of the lens is shaded by the other part of the vehicle, then, could it pass the regulations or not?
Your kind assistance and earliest reply will be highly appreciated.
Sincerely yours,
Yueh-An Chen Division Head Planning Division