lighting industry high bay news,lightingdigest.co.uk
The inherent versatility of Holophane's Optimised Lighting Operating System (HOLOS2), which enables dimming of high intensity discharge light sources, is proving invaluable in a range of applications, including aircraft hangars.

This is clearly exemplified by two recent projects, both carried out in conjunction with Balfour Beatty Engineering Services.

RAF Brize Norton
Two new hangars at RAF Brize Norton had a need for controllable metal halide lighting, with very specific control requirements.

"The metal halide luminaires are arranged in clusters of four, each of which is dimmed during normal circumstances to run at less than 100% of full light output," explained Gareth Weale of ARUP. "If one of the four lamps fails, the other three are automatically ramped up to 100% output to maintain illuminance levels," he continued.

Extensive rooflights on both hangars also enable some daylight control and each hangar is divided into six zones, each with its own photocell to provide independent zone control. Through the day, as the distribution of daylight in the hangar changes, the lighting in each zone is increased or decreased, as appropriate, to maximise the use of daylight and minimise electricity consumption.

Lighting zones can also be controlled manually, with a separate three-way switch for each zone enabling the lighting to be set to 'off', 'automatic' or '100%'. The positioning of the switches on the control panel has been configured by Holophane to mirror the layout of the zones in the hangar so that users can see at-a-glance which switch controls each zone.

In another project, a new hangar, capable of housing 28 aircraft for maintenance, required a controllable lighting solution that could be adjusted in line with levels of maintenance. It was also necessary to maintain lighting at suitable levels for the video smoke detection system used in the hangar.

As this hangar receives no natural daylight, it was also important to meet the lighting requirements with minimum energy consumption. The HOLOS2 system proved ideal to deliver the level of control required for the metal halide lighting.

The lighting control system is designed to ensure illuminance levels of 500 lux while maintenance is being carried out, and this is reduced when no maintenance is being carried out and at night by dimming the lighting. This hangar is divided into two zones and the lighting can be controlled automatically or using a manual override.

The manual switching configuration enables each zone to be set to one of three settings: 'maintenance' for full lighting, 'parking' when no maintenance is being carried out and 'night time'.

In both hangars, the ability of HOLOS2 to deliver smooth, stepless dimming of metal halide sources with imperceptible colour temperature variation, ensures that lighting adjustments are very subtle and do not distract the maintenance crews.

The HOLOS2 system is also quick and easy to install, using a simple two-wire bus system with just one control cable per 64 luminaires and with the same bus system also being used for control devices. There is also ample capacity and capability in both systems to control any future DALI-based fluorescent lighting, should the need arise.

Contact details