Magnetic vs. Electronic Ballast
Magnetic ballast are now prohibited per EPACT 2005, but are still in operation in the majority of buildings in the US. They are the main reason for concern in a retrofit lighting audit. You have to be aware that magnetic ballast are a high consumption of energy element in a building and can be more susceptible to power quality issues than electronic ballast. They work operate with 60Hz frequency witch they have to increase by vibration to excite the lamps gases and keep them on. This vibration causes a high pitch noise that can affect hearing and cause power quality problems with computers and other electronic components that are sensitive to RFI noise. Electronic ballast convert 60Hz frequency to MHz frequency without the noise. Some engineers in buildings may have concerns with Total Harmonics Distortion and electronic ballast. They should not, because it has been shown that magnetic ballast also produce Harmonic Distortion and the technology used in the majority of electronic ballast is well bellow the percentage recommended by IEEE.
The main conclusion is that you are way better off, making the change or retrofit with electronic ballast, than having a high energy consuming fixture.
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