The Zhaga Consortium, a global association of lighting companies that is standardizing components of LED luminaires, has finalized a new specification that helps to bring the Internet of Things (IoT) to outdoor LED lighting fixtures. The specification, known as Zhaga Book 18, makes it easy to upgrade LED fixtures by adding or changing 24V modules that provide sensing and communication capabilities.
Smart LED lighting fixtures with sensing and communication capabilities can significantly improve the efficiency, maintenance, and running costs of outdoor lighting networks. In this period of rapid IoT evolution, there are many unanswered questions about the correct choice of sensing technologies and communication protocols that future smart-lighting networks will require. However, outdoor LED lighting fixtures are being installed right now, with an expected lifetime of around 20 years or more, and the cost of retrofitting can be prohibitively expensive.
Zhaga’s Book 18 specification solves this dilemma by enabling future-proof luminaires that can be upgraded as technologies evolve.
Book 18 defines a standardized interface between a receptacle on the exterior of the LED luminaire and a sensing and communication module that fits into the receptacle. The standardized interface means that the module can be easily replaced in the field, allowing the luminaire to be upgraded via the addition of new smart capabilities. Additionally, the luminaire can be shipped with a blank cap in the receptacle, allowing a module to be field-installed later, if required.
Book 18 Ed.1.0 defines the mechanical interface between the module or cap and receptacle. However, many non-critical aspects are not restricted by the specification, allowing vendor differentiation and design innovation.
The specification has recommendations for the electrical interface, which features a 4-pin connector. The recommended pin assignment enables the required 24V DC power supply, as well as DALI control and a general Logic Signal Input (LSI).
Book 18 Ed.1.0 offers a number of advantages compared with the existing ANSI/NEMA standard C136.10-2010. This describes locking-type photo-control devices and mating receptacles, and is used mainly in the USA and the UK. Book 18 Ed.1.0 enables modules with a much smaller footprint, which in turn will allow greater design flexibility for the luminaire. Also, the Zhaga specification uses 24V rather than mains voltage.
More information on Book 18 Ed.1.0 can be found on the Zhaga website at www.zhagastandard.org/books/book18.