Night-time dimming outdoor
Controlling the level of light makes it possible to save a lot of energy. There is often less need to have fully lit streets and other outdoor environments late in the evening and during the night. But switching off lights can make people feel unsafe
With the aid of lighting control, major energy savings can be made without the need to switch off lights completely and create a sense of insecurity.
The various systems we use for lighting control outdoors are integrated into each luminaire’s electrical ballast and take care of themselves. Nor is there any need for external accessories to make the lighting control work.
The control units are pre-programmed and maintenance-free. Luminaires with night-time dimming also require no additional investments in or modifications to infrastructure.
The systems we are talking about have many different names in the industry. We choose to call it what it is – night-time dimming.
Night-time dimming 1
Light levels: 100 percent and 50 percent.
With Night-time dimming 1 the installation is adjusted down from the light cycle’s centre point and six hours ahead. When six hours have passed, the installation is adjusted up to full level.
The system calculates the light cycle’s centre point when the installation is on, and then adjusts down from 100 percent to 50 percent over six hours from this centre point. When six hours have passed, the installation is adjusted back up to full level. This can result in energy savings of up to 20 percent.
The system calculates the light cycle’s centre point via a lux relay in the existing system which measures the brightness of the natural light and determines when the light should be switched on and off. This is then done automatically by the system every three days.
In December the light installation switches on at 3 pm and switches off at 9 am. This means that the light cycle is 18 hours long. The centre point is therefore midnight. This means that the light level is at 100 per cent between 3 pm and midnight. The light is then adjusted down to 50 percent. At 6 am the light installation is adjusted back up to 100 percent until 9 am, when the light installation switches off completely.
In June the light installation begins at 10.30 pm and switches off at 3.30 am. This means that the light cycle is five hours long. The centre point in the period is therefore 1 am. This means that the light level is at 100 percent from 10.30 pm until 1 am, when the light is adjusted down to 50 percent. As the total light cycle is not long enough, the upwards adjustment phases are made shorter. The light installation will then switch off completely at 3.30 am without having been adjusted up to 100 percent.
Night-time dimming 2
Light levels: 100 percent and 50 percent.
The Night-time dimming 2 system adjusts the output down from two hours before the light cycle’s centre point and a total of eight hours ahead. When eight hours have passed, the installation is adjusted up to full level.
The system calculates the light cycle’s centre point when the installation is on. Two hours before the centre point and a total of eight hours ahead, the installation adjusts down from 100 percent to 50 percent. When eight hours have passed, the installation is adjusted back up to full level. This can result in energy savings of up to 25 percent.
Custom night-time dimming
Light level: dynamic (max. five levels).
Custom night-time dimming is flexible and can be programmed entirely to suit the customer’s wishes. The levels and periods set can, for example, be based on traffic intensity and presence at the location as well as the type of area in which the luminaire is fitted.
Light level: dynamic (max. five levels). The system offers up to five flexible light levels which can be set for optional time periods. This allows for extremely low light levels in the middle of the night, higher light levels when needed and medium light levels during the transition periods. The system works around a centre point that is based on the total time for which the luminaire is lit. Energy savings depend on light level and time.
Products from Fagerhult can be equipped with various dimming options and combinations between CLO and night-time dimming.
|-461||DALI and CLO|
|-462||Night-time dimming 1|
|-463||Night-time dimming 2|
|-464||CLO and Night-time dimming 1|
|-465||CLO and Night-time dimming 2|