Mount Lighting, specialists in commercial and emergency lighting, explain how utilising a built-in occupancy and light-linking detection solution can save money on energy costs.
Put simply, occupancy detection involves using Passive Infra-Red (PIR) and Microwave detection to help cut down on unnecessary energy consumption. Microwave detection is a newer and more advanced occupancy sensor than the PIR – it works by emitting high frequency electro-magnetic waves and then receives their echo.
The sensor detects the change in echo from the slightest movement in the detection zone which commands a microprocessor to switch the light on. This is achieved in a number of different ways:
Level 1 – Once motion is detected the lamp lights up. After a specified period with no movement the lamp then switches off.
Level 2 – Using a dimmable ballast, the lamp will turn on in the same way but will dim down to as low as 10% during absence. This can be turned off after a specified time or remain dimmed at 10% until presence is detected, when full illumination is immediately restored.
Level 3 – Another useful feature is daylight-linking. This means that as well as detecting movement, the controls automatically adjust the lamp output, depending on the light level at the time.
BENEFITS OF DIMMING
● Lower energy consumption
● Reduced energy costs
● Better safety and security
● Eliminates cold lamp start up
● Longer lamp life
Dim and proper
Dimmable occupancy detection is ideal for applications such as stairwells, car parks and corridors where areas are typically only occupied for a small proportion of the day, but where continual illumination is necessary for safety. The graph (pictured above) shows the typical conduction of a luminaire with this type of control.
As described in Level 2, Mount Lighting offers the option to dim lamps down to low level on absence, rather than switching the lamps on and off. This is achieved by utilising a ‘corridor function’ dimming ballast, rather than a fixed output which will dim down the lamp to a low level of approximately 10% on absence. A luminaire dimmed to 10% saves 80% of the energy use and the return on investment can be as short as 10 months.
Mount Lighting also offers a free Energy Saving Calculation tool on its website to see what savings can be made.
