The extra current can be a problem for the building wiring and circuit breakers in situations where there are a lot of fluorescent luminaires. To bring the power factor back to nearly the same as it would be in a resistive load we add capacitors to fluorescent luminaires. These are called High Power Factor fittings. Power factor correction capacitors can also be fitted in the power distribution board instead of on each fitting. These are twin lamp types with one lamp having a leading power factor current leading voltage and one lamp having lagging power factor.
Single lamp fittings of this type are call leading power factor capacitor in series with ballast. This an inductor coil wired in series with a fitting to present a high impedance to ripple control frequencies. When a power factor correction capacitor is included in a fitting HPF models it presents a low impedance to the ripple control frequencies.
This reduces the level of these frequencies and degrades the reliability of ripple control systems. The addition of an inductor blocks the ripple control frequencies from reaching the capacitor and prevents them from being reduced in amplitude. Since January 1, Australian regulations have required that all light fittings comply with regulations concerning the amount of electrical interference produced by the fitting.
Check out xmaslightguy's youtube video too and it is obvious. Yep, even my electronic RS ballast drive 40 watt lamps at 40 watts! Same thing with the 34 watt lamps, runs them at 34 watts, instead of lower.. All else being equal, I have never been too concerned about power factor. The biggest advantage of HPF, even for residential, is the operating current is lower not wattage so that existing wiring is under less load.
Typically, HPF ballasts are brighter because most North American ballasts are for more than one lamp size and the cap keeps a more constant lamp current, whereas, a NPF ballast has to under-drive a larger lamp to properly run a smaller lamp.
A HPF version of the same size ballast will drive both lamps at nearly the same current. Interesting note: the older PH 40w single lamp NPF ballasts drove 40w at full output and would overheat and overdrive a 30w lamp, therefore, they were 40w only. I've seen both residential and commercial HPF designed to run lamps at lower output for energy savings.
Yes I know this is an old topic, but it's still a valid one. I always try to include a PFC capacitor in any installation, for completeness if nothing else. I build demonstration displays amongst other things, and I like them to look complete. The capacitor may not be strictly necessary , but I will always do my best to include one. The PDF isn't exist anymore, but I think that in a rapid-start ballast, the power factor affects the lamp performance, since these ballasts uses the capacitor as the ballasting component.
There is no "electrical" relation. In many power strips the clearance between conductors is not good enough and this arc will turn into a flashover across the V supply If there is concern with the current draw of the luminaire using few luminaires on a branch circuit or on a long extension cable of thin gauge , then it's better to include the capacitor.
Quote from: Ash on April 22, , PM. Pages: [ 1 ] Print. Read times. That article actually has a few errors. I should have posted this one instead. I find this one to be more accurate. RTP is a rapid start.
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