We have a project with 2 different pendant fixtures that the Owner really wants to use - but they are designed for MR-16 and incandescent lamps.
It appears that, according to ASHRAE 90.1-2007, regardless of the lamp used in a fixture, LPD is calculated using the maximum rated wattage for the fixture.
Is it correct that a fixture designed for use with an MR-16 or incandescent lamp, but utilizing an LED lamp, must still use the MR-16 or incandescent wattage (maximum rated) in energy calculations? If so, is it possible to use a low amp breaker just for those fixtures to limit the available power, thereby lowering the LPD?
Thanks!
Bill Swanson
Sr. Electrical EngineerIntegrated Design Solutions
LEEDuser Expert
734 thumbs up
November 9, 2012 - 4:45 pm
You are correct. The wattage is based on the maximum that can be installed in that fixture. Some companies will add at the factory a UL sticker with a lower maximum wattage listed. The fee for this is negligable since it's just a sticker that's changed. But if you can get a company to do this then you can use the new lower maximum wattage.