Dimming lighting loads can be quite tricky, especially when it comes to LEDs; many lack smooth dimming transitions and step-through from one level to the next. Testing fixtures and the driver together is an essential – and often overlooked – step to avoid unnecessary headaches associated with dimming lighting loads, particularly when it comes to architectural installations.
Coventry Lighting owner John Coventry called upon ETC’s testing services in the middle of a big lighting installation for the newly redesigned concert hall in Gaillard Auditorium in South Carolina, US. “ETC responded unflappably to my frantic phone call,’ explains Coventry. “They had a great response time.’
The LED fixture that Coventry wanted to test was from Cooledge Lighting, a manufacturer that specialises in LED light sheets – paper-thin, flexible LED light strips that can be fixed to unusually-shaped objects and walls to create custom lighting fixtures. “The LED sheet and driver are being used as the light source inside custom sconces, which are being installed in a new concert auditorium,’ says Coventry. Therefore, it was critical not only for the fixture to dim smoothly from level 0 without noise, but it also had to light at a steady level when at full or partial power.
The Gaillard Auditorium installation already contains ETC Sensor3 and Sensor+ SineWave dimmers and ETC LED luminaires, making ETC a no-brainer when it came time to test the new Cooledge fixture. Coventry also already had the exact fixture and driver specified from Cooledge that required testing. “Coventry’s preparedness helped eliminate a lot of extra troubleshooting that often occurs during the testing process,’ says ETC project manager Ted Ozimek.
The fixture was tested on an ETC Sensor3 DRd dimming rack, with exceptional results. “The Cooledge driver and LEDs exceeded expectations based on the dimming performance. They dimmed much better than most and without flicker at the low end.’ This is rare, according to Ozimek, who says that most LED fixtures of a similar nature do not have smooth dimming, particularly from a zero level. This often looks very visually displeasing to an audience member or viewer.
After testing was complete, plans were made to implement the fixture into the existing dimming system in Gaillard Auditorium. “We managed to make adjustments to the ETC dimming system to dim the new Cooledge LEDs, which required a 0-10 four-wire system,’ explains Coventry, who says he was very pleased with the fixture and its performance.