posted by III: Tuesday, August 05, 2008
due to recent emails and information regarding the Energy Independence and Security Act of 2007 - there are certainly going to be a lot of questions and points of clarification that folks will be asking. Aside from the main lighting requirements, (CFL vs. Incandescent, etc), there is the requirement to increase efficiency in probe-start metal halide ballasts (to 94%) and pulse-start ballasts (to 88%), It might be worth asking/reviewing/discussing (in layman's terms) a few points;
a) what is the difference between Pulse start and Probe Start? (besides a pink socket?)
b) does this just apply to ED-17 lamps?
c) Most architectural lighting fixtures have begun to move away from ED-17 and towards T-6 lamps, what types applications and/or industries need to use probe start ballasts?
Labels: ballasts, Energy Act 2007, metal halide
For some time, lamp manufacturers have been using the pulse-start (PS) arc tube technology in lamps lower than 150W. This legislation sets a minimum energy efficiency requirement for metal halide systems from 150W to 500W; currently available probe-start lamp-ballast systems will not meet this standard; thus the shift to PS.
The Light Research Center has a nice write-up on the differences between the two technologies at: Pulse-Start versus Probe-Start
It's not that the legislation requires PS be used, it says the other stuff is too inefficient given our current environmental and energy situation. NEMA has some good comparison information but in summary we are looking at 79 lumens/Watt (l/W) versus 99 l/W for the lamp and ballast only. When we factor in the simple fact that PS lamps emit light longer, (0.72 LLF versus 0.59) we have 51 l/W versus 85 l/W). THAT IS 67% MORE LIGHT THAN THE PROBE-START. Now you may see why Bagby has been using this source on most drawings for over a year.
It is fair to say that every lamp is impacted, but again, most anything below 150W has been pulse-start for years and meets the efficiency (it's actually efficacy but let's not get picky) standard we have to meet. The shape of the lamp certainly had no impact on the arc tube technology in it. High wattage lamps (that most folks would say were used for sportslighting) are not affected. It is not clear why that is the case since those sources have the same low efficacy as a 400W probe-start system. I guess that gives us something to look forward to in the future.
August 5, 2008 9:42 AM
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