Lighting in Design Q3 2022

• The use of motion sensors is a common method to reduce energy consumpt ion however due to the conditions within hot aisles - high ambient temperatures and excessive airflow – completely rules out the use of motion sensors. Frequency sensors such as Microwave or Ultra-sonic detect any type of movement. People, animals, plants, blinds, curtains etc. Even air movement when there is enough of it thus in this application increases the risk of the lights staying on. Passive infrared sensors pick up changes in temperature. In this case, the high ambient temperature interferes with the sensors ability to detect a person entering the aisles thus increasing the risk of lights not turning on at all. • Cold aisles are not as tricky but still present their own challenge, excessive airf low. Still too much to use a frequency-based sensor however the use of Passive infrared sensors can work well as the ambient temperature is low enough where the differential between air or surrounding material and a person is enough to trigger the sensor. • Another way of maximizing energy savings is by implement ing a technology cal led corridor function. This requires dimmable LED fittings coupled to an appropriately selected motion sensor for the required application. Rather than completely turning the lights off when no movement is detected and thus adversely affecting CCTV and user comfort, the luminaires are dimmed to a lower intensity and brightened when a person enters the environment. • An often-overlooked benefit of implementing control strategies is that they reduce the operational hours and temperatures of the light fittings and thus increase their life span as well as reduces their lumen depreciation. Q: How do you ensure that lighting is able to support video surveillance usage even when the data centre is not occupied? A: For this to happen, minimum light levels need to be stated. Furthermore, a corridor function can be implemented where the luminaires dim down to a certain percentage when there is no occupation. Lighting designers should ensure that high quality drivers are used with no flicker to ensure crisp clear video, and use minimum CRI 80 LED to ensure proper light quality

each other with the cold air getting pumped into these rows.

Q: Advantages of LED lighting for data centres include immediate energy, instant illumination with no warm-up, flicker-free light performance, and being cooler to run. What are the other benefits of LEDs for these humid, data-critical environments? A: Advantages of LEDs include: • Longer Lifetime due to less lumen depreciation. • Less maintenance due to longer lifetime. • Aesthetics: The ability to incorporate LED lighting into modern architecture. • Efficiency: Most of the energy consumed by the luminaire is converted into light. • Ability to handle temperature fluctuations. • Controllability of LED. • The quality of light produced. Q: Data centres are known for virtualisation and automation among other things; how does lighting assist in these areas? A: Lighting only the area where the light is needed, reduces the energy consumption dramatically especially in hot aisles. Lighting in hot aisles only on when needed reduces risk of premature failure, and improved safety through better illumination. Q: How are motion sensors used in data centre lighting? • Imp l ement i ng cont r o l s t r a t eg i e s i nto applications is a great way to reduce energy consumption. Not only is this beneficial for the electricity bill but this also plays a large role in reducing the connected load when generators or UPS systems need to operate. • Selecting control strategies to implement into Data Centre’s can be particularly difficult as areas such as hot and cold aisles present unique challenges.

Q: What level of lux is recommended?

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LiD Q3 - 2022