Opportunity KNX

Instantly recognisable by its distinctive red brick exterior, the British Library was the largest building constructed in the UK in the 20th century. And with good reason. If you viewed five items each day, it would take you 80 000 years to see the whole of the library’s collection.

Situated in London’s St Pancras, the bustling public building is famous for its 225-seat auditorium, meeting rooms and reading rooms. More than 16 000 people use the collection each day. It came as no surprise to learn that when the library’s existing lighting control system needed replacing, minimal disruption during installation was pivotal to the specification.

After careful consideration, the British Library opted for a lighting control system based on KNX (formerly known as EIB – European Installation Bus). It was fitted by specialist intelligent building controls system integrator Andromeda Telematics.

KNX is an international control standard for intelligent buildings. It enables the integration and programming of a range of products from different manufacturers using one software tool. All products are tested for compliance, ensuring they operate together on a single network.

As well as ease of installation, KNX systems are non-disruptive in the long term. KNX offers adaptability via simple reprogramming with a laptop, and there is often no need for rewiring or added expensive hardware.

Future-proofing was a major consideration for the library, as the building is designed for a lifespan of more than 50 years. Makers who adopt the KNX standard guarantee that all new KNX products will be fully compatible with any existing installations. This means that maintenance and spares should not be a problem.

The library’s total floor area of more than 112 000 m2 is spread over 14 floors, nine above ground and five below. Its basement extends to a depth of 24·5 m. The lighting solution provided connects all the risers in the basement with a KNX bus that extends throughout the building. Connecting the lighting control into one system over such a large area was achieved by providing a backbone using IP over copper, and in some areas over fibre-optic media.

Intelligent building technology has moved on in leaps and bounds since the library’s previous control system was fitted and, using KNX, many additional functions were provided, including the use of Digital Addressable Lighting Interface (DALI) controls.

DALI is a worldwide standard communication protocol for digital lighting control. It was established by a group of European ballast manufacturers to support open architecture, so that devices from any manufacturer could be interconnected in a digital lighting system. However, DALI is meant only for communication in lighting systems.

Building management systems (BMS) typically have unlimited expansion possibilities, whereas DALI’s are limited to 64 addresses. Up to 16 light levels can be programmed into the ballast memory, and each ballast can belong to as many as 16 distinct groups, allowing different lighting scenes for study spaces and other room applications. The system is suitable for both simple and complex installations, and wiring and configuration is designed to be kept to a minimum.

Head-end graphical packages providing time-based scheduling, manual override control functions and field status such as real-time lamp failure were incorporated into the new design, together with facilities for constant light control and energy reduction. Research has shown that effective use of lighting control can result in energy savings of 30-40%.

In addition, blind and screen controls were also installed in conference and meeting rooms.

Andromeda Telematics provided systems integration for the project. The company is one of many integrators that are members of KNX UK, providing KNX-driven building control systems. Due to the KNX philosophy of open protocol with a common software configuration tool known as ETS, Andromeda Telematics was able to train the library engineering staff to maintain and reconfigure the system themselves before giving the British Library full control over the system.

Lighting is one of many examples of how KNX systems can provide centralised control for building systems. KNX-compliant products are also available for control of hvac equipment, intruder alarms, audiovisual systems, blind/solar control household appliances and many other building services. Integrators and contractors can provide total control solutions by bringing together these truly interoperable products.