Can HID sources be dimmed?
Yes. High Intensity Discharge sources can be safely dimmed down to approximately 50 percent power and 30 percent of full light output using special ballasts and control devices. But, it should be noted that as HIDs are dimmed, the color shifts. Therefore, HID dimming is generally only suitable in areas where color rendering is less important. Also, keep in mind that existing HID luminaries must have new ballasts installed to permit dimming. Doing this is often more expensive than the complete HID lighting system. Before installing dimming in HID systems, consider fluorescent replacements. New fluorescent fixtures using four to six high output T5 lamps have been designed for “high bay” applications up to mounting heights of 30 to 40 feet. These fluorescent systems are much more efficient than ordinary HID lighting, allowing maximum power to be reduced by 20 to 25 percent. The big advantage of fluorescent technology is the ability to switch lights instantly and in pairs. This permits mor
