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CFL equivalance wattage changes

Discussion in 'Lighting' started by Andrew Gabriel, Feb 1, 2012.

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  1. I notice a sudden recalculation of the equivalent filament light output
    ratings on the packaging of all CFLs in the shops in the UK.
    They are now mostly claiming almost the 1:4 ratio I've always stated,
    rather than the completely bogus 1:5 and 1:6 ratios they've been
    lying about for years. I don't know what triggered this change, but
    it was far too long coming.
     
  2. Andrew May

    Andrew May Guest

    I noticed that at the weekend. There no longer seem to be any CFLs
    available that claim to be equivalent to 100W tungsten.
     
  3. Tomsic

    Tomsic Guest

  4. Brian Gaff

    Brian Gaff Guest

    I think the old ones simply took the complete light output and the newer
    ones take account of the way they eye perceives light and so the frequencies
    produced do matter. Also I've been told newer ones seem to be whiter and get
    full output faster than the old ones used to. Maybe they had a job lot of
    crap phosphor to use up that gave off lots of light but not in the right
    places in the spectrum!

    Brian
     
  5. There never were real 100W equivalents in the supermarkets
    (which only stock lamps up to around 18W), but of course
    they used to claim to be, which was probably the main cause
    of the complaint that they were too dim when people tried
    their first one. If you go to more specialist outlets (often
    mail-order), then there are CFLs available up to 100W (native)
    and more.

    The only honestly marked 100W equivalents I've seen before the
    recent change are the Feit ones stocked by Costco - 23W large
    spiral tube which is genuinely equivalent to an old 100W (and
    I've found to be very good in all other respects such as long
    life at high temperature running, sustaining full light output
    during life, instant-on). Only problem in some fittings will be
    physical size, as efficient light output demands a large spiral.
     
  6. PeterC

    PeterC Guest

    Morrisons stocks 30W and very nice they are too. Don't get silly hot even
    balls-up in a shade, possibly due to PFC.
     
  7. PeterC

    PeterC Guest

    I wonder if it was based on the output of the straight tube and didn't allow
    for some of the light shining through 3 layers.
     
  8. It was based on the output of softone lamps, which had a painted
    glass coating, which lost 20% or more of the light. Almost no one
    used these - it was basically a way of misleading people about
    the light output of CFLs, but it badly backfired on the industry,
    because everyone could see they were lying, and it had the effect
    of making out the lighting industry to be dishonest in the public's
    eyes.
     
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