Intelux controllers for lights intelligent management in a factory

BACKGROUND

The plant set up in Urago d'Oglio (BS) for DURPRESS, company specialised in die-casting parts for lighting and technical equipment, is a fine example of "intelligent" lighting control thanks to implementation of the Intelux system. The plant is made up of two large independent sheds covering an overall area of 8600 m2. All the areas have long wide sky lights, which means that there is a considerable amount of daylight available, even during the winter. The plant has 260 fittings, equipped with 250Whigh pressure sodium lamps .This choice was made because the light sources are, in physical terms, very high up. The overall installed power is 70 kW.

THE SOLUTION

The lamps are sectioned along 20 three-phase dorsal lines. Each dorsal is fitted with three 5,8 kVA Intelux controllers, one for each phase with a shared neutral, controlled by two control units, one for each shed. The lighting level of the two areas is guaranteed by internally positioned light sensor photocells, whose task is to compare the light component produced from natural daylight and artificial lighting source and then send continuous signals to the control unit, which regulates the controllers. Hence light flow coming from artificial source can be modulated according to available daylight and the required lighting level during the various production phases is kept constant. The work plant runs on a daily and nightly shift basis. So, in order to optimise the energy saving, a 4-step control was installed (95%, 65%, 40%, 25%). This also consents a reduction in energy uptake in the hours that do not require total use of installed power and the required level of lighting can be chosen according to necessity.

BENEFITS

The average energy saving was calculated at 54%, and the results acquired during testing period carried out in December 1999 inferred, for this plant, an investment return of under two years.