Actual equivalency is going to be somewhere from 240W to 280W. You're looking at 80W equivalency per 20W CFL, although if they are large spiral ones, they are a little better. Ignore the equivalency on the packaging.
Do you really mean PAR38? AFAIK, they are all ES, not BC.
4 or 5 foot fluorescents with high-frequency electronic ballasts. Instant-on, long lamp life, no flickering.
Think that's a bit of an urban myth with present day tubes - the phosphors have a longer 'persistence' than once. But the certain way is to use fittings with electronic ballasts - these switch at approx 30,000 times a seconds rather than 100 as older ones do. You could fit new ballasts to the existing fittings if you find a cheap source for them.
Yes. sorry, it's Par 38 - got the bayonet wrong - it's Edison Screw. (I'll go and fall on my bayonet ;-))
Toom
When you get up to about 5000 times a second, you're switching faster than the decay time of an excited mercury ion, so the discharge becomes continuous (and the tube becomes 5-10% more efficient). As you say, all electronic control gear switches at well above 5000 times a second (there are further advantages in minaturising the control gear by going up to higher frequences).
,
They are nowhere near as popular in this country as they are in the US, and in the US you can find metal halide retrofits, but I've never seen those here.
You can get CFL retrofits if you search online. I haven't used them, but they probably aren't anywhere near as good as the real thing. I would guess a much wider beam spread, and lower beam intensity.
What's the lamp being used for? Most of these are hard glass lamps for outdoor use in the rain, and if you are using outdoors, you'd need to make sure any retrofit was also similarly waterproof.
If it doesn't need to be waterproof and the lampholder well supports the bulb (as opposed to a sealing collar against the glass), then a
23W GE Genura will well outperform an 80W PAR38 (it's about 110W equivalent). The Genura is really an R80 replacement, but the PAR38 is a physically larger bulb, so the Genura would fit in most cases, unless the exact bulb shape is critical. The Genura requires good cooling ventilation for long life, and you want long life because it's expensive. It works in a completely different way from most CFL's, and a side effect of this is it doesn't suffer reduced life from frequent switching on/off, but it does take a minute to run up to full brightness when cold. It's a floodlamp, not a spotlamp. B&Q stock them.
Many thanks for the info - It's a lighting rail on a kitchen ceiling (circa 1982) which has three moveable/directional fittings to allow light to be directed as appropriate. I admit I haven't looked to see if standard reflector lamps (will these still be available?) will slot into the long narrow fittings for the connectors of Par 38 - maybe they will - but was interested in whether the replacement had been addressed and/or whether switch-in plastic connectors to the rail might be available for another type of lamp. All I can say is that when I ask in shops, they just shrug their shoulders.
Toom
B&Q do electronic ones with plastic diffuser and tube for about £20 for
5ft/58W
If you're after the sort of lamp that has a sort of parabolic-ish round-ish shape silvered at the back (stem) end to throw light forward with thin glass like a regular light bulb, then I've seen CFL equivalents. They seem to be a CFL in a polycarbonate enclosure that's the shape of the glass in the incandescent version. I've got one in a clip-lamp holder for use as an inspection/worklight - the polycarbonate enclosure protects it against knocks to some extent.
I've seen them at Morrisons - I don't know if they still have them but they can't be hard to find.
I am trying to get the Osram Halolux R50 28W at a reasonable price; noone does them locally (and I have asked Osram about it) and postage is killing me from the cheapest place I could get them:
I did use a similar GLS replacement in my bathroom wall-fitting and it seems to work well, by the way.
Kostas
Many thanks - I'll look into it
Toom
That sounds quite reasonable.
The 'old' ones flickered at 100Hz, so well in machine speeds; the 'new' are, IIRC, 30kHz - if machines are at that speed...!
There was an old chap at work who helped to install Britain's first tube. It was over a lathe. The operator tried to use the chuck when he thought it was stationary!
Bah - Just had 2 CFLs blow (as in dead, as in parrot) in 2 days. One was 3 months old and the other a couple of years.
These are "proper" makes, not Tesco Value. Probably the electronics has gone. If this is what we can look forward to, it's not very promising - or green.
In the office here, which gets the most use, they last about 8 months. Incandescents used to be about 6 months.
Frankly, they are about as green as fuckoff windmills. I.e. you pay four times as much for a marginally better situation, which, in the overall scheme of things, is pissing in the ocean.
It probably takes as much oil to ship them in from China as they save.
Perhaps some people's preference for incandescent light bulbs has been boosted by the Health and Safety Executive statement that ?in a limited number of circumstances UV (ultra-violet) exposure from CFLs can exceed guideline levels. CFLs should not be used in close proximity (distances of less than one foot) to people for longer than one hour?. ?The risks can be reduced ... by using a double-encapsulated bulb.? (LAC 60/8, February 2009.)
Supply and demand.
I managed to get 20 of the lamps from the wholesalers. The rest are presold.
Adam
>
Only place I have them is as outside lights - and the life there is very much longer than incandescent. Perhaps it's a cooling issue - the electronics probably dislike getting hot. And of course the makers test them under ideal situations.
Dave Plowman (News) coughed up some electrons that declared:
3 - it's three now. Bog lamps just gone. At least that one was about 3-4 years old.
That's what I thought. And they've been doing them for years, so it's not just temporary mis-pricing.
My sparks mate reckons that's about the going price from wholesalers.
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