Applications

Circuit-wide dimming

The Opt-i-Mizer controllers can be fitted to either the supply or load side of the distribution board and with an extensive product range, the units can be used to control the load on almost all sizes of lighting circuit . The Opt-i-Mizer is a step down voltage controller that reduces the supply voltage to the lamps once the lamps have been struck. In contrast to some other systems available the controllers are not limited to dimming just a few lamps but can be used to dim up to several hundred lamps, without the need to change either the type of ballast or lamp fitting. By reducing the load voltage then the lumen output of the lamps is also reduced, the level of reduction being a function of the starting voltage and the specific characteristics of the lamp ballast. Generally, the relationship between lux and the total energy saving induced by the voltage reduction is approximately 1:1, although at extreme values this relationship can be less.

Energy Saving through Daylight Harvesting

Opt-i-Mizer Controls

The Opt-i-Mizer unit includes two remote control functions that can receive commands from a variety of sensors and timers. By utilising lux sensors the controller can be used to capture daylight in two ways, first by adding dimmed artificial light in marginal daylight conditions and second, by switching the load to ‘OFF' if full daylight conditions permit. When the level of natural light has fallen below the minimum pre-set value, the lighting installation is switched ‘ON' by the first LUX sensor to give full artificial light. If the natural light level increases, but not yet to the full illumination level required, then the second lux sensor switches the unit into ENERGY SAVING, giving DIMMED, lighting levels. When the natural light levels are sufficient to maintain illumination without artificial light then the lamps are switched ‘OFF'.

The chart below shows a typical contribution that can be made towards the total energy saving package from daylight harvesting and from dimming, based upon voltage control. The example assumes that savings are already being made in the peak daylight months of June and July when no lights are switched on.

In this example, daylight harvesting contributes 15.5% saving and voltage control 18% (net of the daylight savings) to give an overall result of 33.3% energy saving.