L.E.D. Signal and Marking Lighting Devices J1889_201503

DOI: https://doi.org/10.4271/J1889_201503

Issuing Committee: Signaling and Marking Devices Stds Comm

Publisher: SAE International

Pages: 7

Rationale: Current definition of photometric stability and commonly used procedure for testing LED functions greatly penalizes LED lamps in a production environment. Changes recommended to J1889 will expedite production testing without compromising accuracy. This version will describe a procedure to expedite testing but will allow testing to former J1889 methods. Section 2 updated to meet SAE standards Section 3.2 – LED definition changed to match J387 Section 3.7 – Removed Section 3.8 - Clarified Photometric Stability definition and harmonized with J2650. New definition allows photometric data to be taken within the 15 minute stability box, instead of after. To maintain good accuracy during photometry the allowed stability drift is set at ±3%. Since section 3.7 was removed, photometric stability will be re-numbered to section 3.7 Section 5.1.1 - Removed extra performance requirement of photometric check for lamps not fully functional. This is covered in J575 and J2139 Section 5.1.5 Renumbered to accommodate changes. Clarified test point to use for ratio measurement because some functions do not have significant intensity at H-V Section 5.1.5.1 - Clarifies use of SAE J1330 Section 5.1.5.2 - Adds statement lamps must be stabilized for test Section 5.1.5.3 - Was added to provide procedure for testing all lamps at stabilization. Section 5.1.6 - Removed warpage as it is covered in lamp level testing Section 6.1.1 Removed extra performance requirement of photometric check for lamps not fully functional. This is covered in J575 and J2139 Section 6.1.5 Simplified requirement definition and included the option to flash function that flash during operation. Section 6.1.5.1 Removed steady burning language, included in 6.1.5 Section 6.1.5.2 Removed intermittent burning language, included in 6.1.5 Section 6.1.5.3 Re-numbered to 6.1.5.1 Section 6.1.6 Removed warpage requirement as it is covered in lamp level testing Section 7.2 was added to provide a method for predetermining photometric stability. Section 7.2.1 Reference to section 3.8 was changed to Section 3.7 to reflect numbering change Section 8.1 - Removed Section 8.2 - Numbering changed to 8.1