BEKA Schréder is proud to have supplied the LED lighting solution for the Huguenot Tunnel near Paarl, Western Cape. It is South Africa’s longest road tunnel. This installation will result in energy, maintenance and cost savings. The upgrade also has positive impact on the safety of road users.

The Huguenot Toll Tunnel provides a route through the Du Toitskloof Mountains which separates Paarl and Worcester. The 3,9km long tunnel was opened in March 1988, and is 11km shorter than the route across the pass. According to the Average Annual Daily Traffic (AADT), more than 12,000 vehicles travel through the tunnel daily.

It was decided to replace and upgrade the tunnel’s old fluorescent lighting and control system for the first time since construction. The requirement was for a complete design, supply and installation solution, including a lighting management system.

More than 6,000 LED striplights and more than 200 LED adaptation luminaires were supplied and are managed by the Advanced Tunnel Solution (ATS) control system.

With the upgrade of adaptation luminaires, the adaptation light levels have improved drastically. This eliminates the black-hole effect when approaching the tunnel during bright daylight, much to the benefit of motorists, who are now able to see clearly when entering the tunnel.

Furthermore, overall uniformities across the road surface of more than 85%, and longitudinal uniformities of more than 95%, were achieved.

Lighting to improve visibility with less energy

BEKA Schréder has developed a customised LED striplight, perfectly suited for this tunnel lighting application. This South African designed and manufactured luminaire incorporates the latest LED technology and consists of an aluminium extrusion body and die-cast aluminium endcaps creating the best thermal environment for LEDs. Various light distributions are offered to provide the right amount of light, exactly where it is needed. The request for a continuous line of light throughout the tunnel was achieved with this unique luminaire design.

The right light where, when, and how it is needed

The tunnel is divided into different lighting zones as per CIE88.

Each tunnel zone requires a different luminance level. The ambient lighting conditions and tunnel entrance as seen by an approaching motorist in the Access Zone is measured by a specialized luminance meter (typically referred to as an L20 camera). The L20 camera provides input to the control system which adjusts the light levels for each zone to follow the CIE curve (as per CIE88). The luminance level at the Threshold Zone is highest at the entrance of the tunnel and then decreases as you move into Transition Zones 1 and 2. Whilst driving through these zones, it gives the eye time to adapt to the lower light levels on the Interior Zone. As this is a bidirectional tunnel, both sides are treated as entrances with L20 measurements controlling the adaptation lighting.

Schréder’s advanced luminance calculation software analyses all aspects of a tunnel environment to provide the right luminance level in all tunnel zones. During the study, the number of luminaires to be installed in the tunnel and their orientation are calculated to create a curve as close as possible to the CIE normative curve for an efficient and economical light installation.

An uncompromising quality

Tunnel luminaires are often subject to harsh environments. Vibrations, flying debris, car fumes, water leaks, and electrical surges can damage luminaires. BEKA Schréder’s manufacturing processes are rigorously controlled in their facilities to guarantee design excellence. Their products are tested and certified in accredited laboratories to resist these harsh conditions and ensure robustness and quality over time.

ATS control system, the solution for tunnel automation management

The Advanced Tunnel Solution (ATS), a co-development between Schréder and Phoenix Contact, is an all-in-one central control system designed to easily manage all tunnel lighting parameters remotely.

The ATS receives a signal from the L20 cameras installed outside the tunnel at the Safe Stopping Distance (SSD), then communicates with all local controllers installed in the tunnel luminaires. It collects information from the LED drivers, but also from hard input triggers installed inside the tunnel. ATS is also capable of switching between relay circuits to ensure long life of LED and driver components in the luminaire, while saving energy.

This innovative tool is capable of constantly adapting the light levels according to specific tunnel conditions like weather, day mode, night mode, maintenance and emergency sensor inputs. The system also controls the light levels using a constant light output (CLO) function, which takes into consideration lumen and dirt depreciation.

This intelligent system permanently monitors the power consumption and reports any BUS communication or power failures. It integrates the initial tunnel lighting study while the industrial BUS system enables individual auto-addressing, to speed up the commissioning process, saving valuable time and resources during installation.

In addition, a Tunnel Control System (TCS) unit facilitates and manages the communication between multiple ATS devices as well as the seamless upstream exchange of data and commands to a higher SCADA level system. Complete redundancy was achieved with ATS to ensure an always ready control system.

Conclusion

BEKA Schréder is delighted to have provided the lighting and control solution for this tunnel. The high-efficiency and long lifespan of the luminaires will enable the South African National Roads Agency Limited (SANRAL) to reduce its operating costs while delivering a much better service for commuters. This new lighting installation has not only improved the driving experience for motorists but will also ensure less closures and hold-ups due to maintenance for a more pleasant commute.

BEKA Schréder, leading local manufacturer of LED luminaires, is part of the Schréder Group. BEKA Schréder locally develops and manufactures sustainable LED lighting products, designed and suitable for local conditions.

BEKA Schréder, in partnership with Phoenix Contact, are very proud to be associated with SANRAL, Innovative Transport Solutions and LEAD Engineering.