Book 10: LED modules for spotlighting

Zhaga Book 10 defines a family of circular LED modules that have a small circular light-emitting surface (LES). Book 10 LED modules can be used with luminaire optics such as lenses and reflectors, and are typically used in spot-lighting applications.

Book 10 contains simplified and harmonized specifications for the LED modules that were previously described in older Zhaga specifications:

  • Book 3 (50mm diameter)
  • Book 11 (35mm diameter)

Book 10 modules can be standalone LED modules, or they can be constructed by combining a COB LED array (defined in Book 12) with an array holder.


Book 3 and Book 11 are published and available for public download.

Book 10 will be published in early 2017.

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Specification details

There are two LED module categories with different outer diameters.

  • D35 = 35mm diameter (formerly Book 11)
  • D50 = 50mm diameter (formerly Book 3)

A range of light-emittng surface (LES) diameters is allowed. Details are given in the Tables below.

The LED modules operate with a separate LED driver (electronic control gear). They are typically fixed to a heat sink using screws. The light output is essentially Lambertian to enable the luminaire optics to shape the application’s desired light distribution from a defined input.

LED module dimensions

Book 10





diameter (mm)

Screw-hole separation

distance (mm)


height (mm)

D35 Book 11 35 25 3.5
D50 Book 3 50 35 7.2

Light-emitting surface (LES) categories

LES category

Minimum LES

diameter (mm)

Maximum LES

diameter (mm)


(Book 11)


(Book 3)

LES 6.3 >4.5 6.3 X  
LES 9 > 6.3 9.0 X X
LES 13.5 > 9.0 13.5 X X
LES 19 > 13.5 19.0   X
LES 23 > 19 23   X
LES 30 >23 30    
LES 40 >30 40