The steel and fabric structures were manufactured and installed by Base Structures with the intention of the three-dimensional wave shapes to link the car park with the original purpose of Cardiff Bay and its connection with the sea. Another visual link with the sea was the requirement for the night time appearance of the wave to be lit using a combination of blue and white lighting.
Particular consideration was taken by Light Bureau in the specification of the fittings and their location due to the close proximity of the very busy entrance to the A4232 Butetown Tunnel. When designing the lighting control solution for this project there were two key elements factored in. The first being the sheer quantity of individual control required for 472 fluorescent ballasts on a single control system; and the second being to be able to programme the visual effects of the sequences in a graphical format and not a conventional "channel = level arrangement".
To achieve these fundamentals, Control Lighting combined the use of a sophisticated DMX visual time line based control playback unit, Pharos Lighting Playback, in addition to converting DMX into 12 separate DALI universes. To achieve the smooth conversion between DMX to DALI interface units, Control Lighting undertook in-depth research before finalising their choice of interface units.
To fulfil the lively night time appearance of the waves, individual control was required per lamp on each of the lighting fixtures that were part of the wave lighting scheme. The chosen lighting fixtures were twin Norka surface mounted IP65 fluorescent fittings with DALI dimmable ballasts. Each fitting comprised a blue and a white fluorescent tube with each fitting modified to take two individual ballasts for individual lamp control.
To minimise on the cable installation the fittings were specified utilising the DALI protocol which enabled a better level of individual control and reporting than other protocols designed for fluorescent ballasts. Careful consideration was taken on the timings of the sequences as well as the impact of the ambient temperature on the lamps and the DALI ballasts. The sequences are recalled automatically using astronomical time clock commands, with manual override facilities also included. The visual result details movement of light intensity utilizing the white and bluefittings across the wave structures in both linear patterns as well as dynamic spiral configurations.
(Jim Evans)
