November 14, 2013…Zhaga has published Book 7 and Book 8 interface specifications for LED light engines. Zhaga is an international organization that is enabling the interchangeability of LED light sources made by different manufacturers. The interface specifications, designated Book 7 and Book 8, can now be downloaded from the Zhaga website.
Book 7 covers a variety of rectangular and linear LED modules with separate electronic control gear that are primarily for use in indoor lighting applications. Book 8 describes a drum-shaped LED light engine (LLE) with integrated electronic control gear, primarily for downlighting applications. Book 7 modules are typically mounted directly into a luminaire by means of screws. Book 8 light engines can be inserted into a suitable socket inside the luminaire. Book 7 LED Light engines (LLEs) are intended to be replaced by qualified personal only. LED modules described in Book 7 have the following dimensions: L28W2 (maximum length 280 mm x maximum width 24 mm; L28W4 (281 x 41 mm); L28W6 (281 x 61 mm); L56W4 (561 x 41 mm); and L6W6 (60 x 60 mm). Within these dimensions, different configurations of LEDs are possible. The only restriction to the light-emitting surface (LES) is that no light is emitted in the direction of the reference plane of the LED module.
Zhaga Book 8 defines the interfaces of a socketable LLE with integrated control gear (a driver). The LLE has a round drum shape with maximum dimensions of 95 mm diameter and 45 mm height. It has a light emitting surface with a width in the range of 59 mm to 71 mm. Zhaga notes that Book 8 is similar to Book 2, except that the LLEs described in Book 8 have larger dimensions. The Book 8 LLE has a PHJ85d-type base with a diameter of 85 mm. The light engine is designed to be locked into a holder inside a luminaire by means of a twisting motion. The use of mechanical fit keying is present to ensure that the luminaire provides the correct mains voltage to the LLE. The light output from the Book 8 LLE is essentially lambertian, which enables the luminaire optics to shape the light distribution to the needs of the application. The light engine is intended primarily (but not exclusively) for use in LED luminaires for downlighting applications.
The Zhaga standard is intended to enable manufacturers to switch from one supplier to another without changing the design of the luminaire. Zhaga contends that this interchangeability can increase competition among suppliers, alleviate the risks of having a single source, and allow luminaire makers to take full advantage of light-engine performance enhancements.
Books 7 and 8 join Books 1, 2 and 3, which are already available for public use. The other approved Books are expected to be published shortly, and new specifications are in development. Zhaga interface specifications are made public as soon as each specification is stable and the certification procedure is fully established. Several Zhaga member companies have already received certification for a range of products that were designed according to either Book 7 or Book 8, including LED modules and holders. The database of Zhaga-certified products can be found on the Zhaga website.