Please note that most compact fluorescent lamp models mentioned in this document take 110-120 volts AC. Magnetic/"iron" ballasted models require AC of a specific frequency - 60 Hz for USA models. Suppliers mentioned by name in this document are mainly in the USA.
In a fully enclosed fixture, where a bit of heat buildup occurs, this lamp can give nearly full light output nearly down to 0 degrees F. (or down to about -15 degrees C.)
Satisfactory operation is likely even in temperatures slightly below 0 degrees F. (about -20 degrees C.), if a slightly to somewhat noticeable reduction in light output can be tolerated.
The Philips SL*18 is claimed to put out 1100 lumens of light. In my experience, my estimate is that this lamp puts out 950 lumens of light when things are going well. A well-known consumer magazine reports even substantially worse results that I find questionable.
I would expect a typical average light output of 850 lumens, which is similar to the light output of a standard 60 watt bulb. This is an average, taking into account effects of temperature and age.
A SL*18 can last 15,000 to 20,000 hours if it is started no more than once every several hours of operation. Its light output will deteriorate significantly after that much use.
The SL/O 18 usually produces a fraction of its full light output when first started. If the temperature is below freezing, its color may be pinkish or reddish. As the lamp warms up, normal color and light output will be achieved. This may take about 3 minutes. This can take even longer if heat buildup in the fixture is needed for the bulb to warm up to an appropriate temperature.
There is a reflectorized version of the SL*18, which has somewhat reduced light output. There is also the "outdoor" SL*18, which I suspect is basically the original SL*18 "Earth Light" with some minor changes.
Philips also has a 17 watt model that is reasonably good for outdoor use. It is a little dimmer than the 18 watt one, noticeably a little dimmer than a regular 60 watt lightbulb.
This model comes in warm color (2700 Kelvin) and cool color / "Daylight" (5000 Kelvin). The part number for the cool color one ends in /50. For nighttime outdoor purposes, the cool color one has an advantage to night vision, and is probably roughly equivalent to a regular 75 watt lightbulb. NOTE: I have yet to test it outdoors at night.
Philips indoor models - 23-25 watt ones are bright!
I have not been as satisfied with other wattages of Philips SL series, although I am somewhat impressed by the one 23 watt unit I have seen so far. (This one may not be suitable for use over a wide range of temperatures). I have noticed that the 15 watt SL lamp with three arching tubes does not like cool drafts.
The Philips SLS 25 watt lamp (did it say 23 watts on the package? It says 25 watts on the base of the lamp) seems impressive. It produces approx. 1450-1500 lumens of light.
News 7/18/98 - Philips now offers a dimmable 23 watt lamp and a 25 watt lamp claimed to produce 1750 lumens.
The Dulux-EL lamps generally produce as much light as claimed. The 15 and 20 watt lamps in particular seem to meet their claims. The 23 watt lamp seems to fall a few percent short of its claim. This makes these lamps the most efficient compact fluorescent lamps I know of. The 11 and 7 watt ones I am less familiar with, but I doubt they seriously fall short of their claims.
That well-known consumer magazine reports the 15 and 20 watt Dulux EL lamps to meet or exceed their light output claims, have higher efficiency than other compact fluorescent lamps that they have tested, and to have reasonable lifetime and reliability.
Here is the light output of these lamps:
7 watt unit - claimed light output 400 lumens, well over that of a 25 watt standard incandescent bulb.
11 watt unit - claimed light output 600 lumens, over that of a 40 watt standard incandescent bulb.
15 watt unit - Light output of 900 lumens is about as bright as a 60 watt standard incandescent bulb.
20 watt unit - Light output of 1200 lumens is about as bright as a 75 watt standard incandescent bulb.
23 watt unit - My rough determination of its light output is 1500 lumens, (estimate increased from 1475 1/21/97) which is about halfway between a 75 and a 100 watt standard incandescent bulb in light output.
(Please note that the lumen claims have increased slightly beyond those mentioned above in late 1996 or so.)
The 2700K versions of the Dulux EL lamps have a color that appears very much like that of a 60 watt "soft-white" bulb. There are slightly whiter and less warm 3000K ones with a color like that of "warm white" fluorescent lamps, and slightly more-pink/less-yellow than halogen lamps.
Some Dulux-EL bulbs come in attractive globes. Note that the globe versions have roughly 10 percent less light output than non-globe versions.
G.E. 39 watt "2D" is a good higher wattage one.
This unit consists of a tube bent roughly into a square 7-3/4 inches wide which plugs into a ballast-adapter. I have yet to measure light output but it slightly exceeds the brightness of a regular 100 watt lightbulb. It is definitely not as bad as most others at being dim when started.
The consumer magazine says that the FLG-15, which seems to be similar except for the shape of the bulb, meets the 700 lumen claim. I have found the FLG-15 to be less widely available than the FLB-15.
These bulbs, or at least the FLB-15, have internal magnetic (iron) ballasts that make a slight buzzing sound that I have sometimes found to be noticeable at home.
One possible good characteristic of either or both of these GE models: I have received a report from someone claiming that a one-piece GE model including a globe lasts extraordinarily long if it is not started frequently. Something like 10 years at 18 hours a day, every day, if started only once a day. I have yet to verify this, but I consider the person who passed this one on to me to be credible.
I have found "Q-Lites" to be unreliable. Of four that I have purchased for myself or others, two intermittently did not work. One had a loose contact in the ballast unit where one of the bulb's four pins fits into, and another had a cold solder joint in the ballast's circuit board.
My bad reliability experiences happened a few years ago; it is possible that quality control has improved.
Lights of America seems to like an "instant-start" circuit that uses series resonance to instantly start lamps that apparantly were designed for preheat starting. I believe that starting can take quite a toll on these lamps, and they should not be used unless they usually remain on at least an hour once they are started.
One characteristic of Lights of America "Q-Lites" is their very warm color. They have an unusually low color temperature around 2500-2600 Kelvin, and the 18 watt one seems to be particularly warm, around 2500 Kelvin. This color is about that of a 100 watt 120 volt 750 hour 1690-1750 lumen standard incandescent lamp operated at 70-75 percent of its rated voltage. You might like this color and possibly want to put up with the "Q-Lite's" disadvantages.
When buying a compact fluorescent fixture or a compact fluorescent unit where the bulb is removable from the fixture or the ballast/adaptor, it is a good idea to get one that uses industry-standard lamps (bulbs) as opposed to proprietary ones.
Replacement bulbs by Philips, General Electric and Osram/Sylvania are industry standard types. You can count on them being available for decades. In most cases you can count on more than one manufacturer making it for decades, so there will be competition keeping prices down.
Some Lights of America replacement bulbs are being discontinued. There are no replacements by other manufacturers for proprietary Lights of America bulbs.
I found this out after being directed by a website fan to the bad news at the LOA page at Budget Lighting.
Stocking up on replacement bulbs will help if you can find them and your stockpile lasts as long as the ballast does - you are out of luck when your stockpile runs out or if your ballast burns out while you have a remaining investment in newly useless replacement bulbs.
Once supplies of replacement bulbs are gone, you are basically out of luck. If you are adventurous enough, you may be able to identify other bulbs of similar wattage, same style and same tubing diameter and do hacking surgery to transplant bases from one bulb to another. (CAUTION - U.L. listing on your fixture is invalid for modified bulbs - fire insurance companies can sue you if a fire starts at an electrical fixture being used other than as directed.)
News 7/18/98 - I have seen two newer Lights of America
true compact fluorescent lamps with impressive light output. The bulbs cannot
be removed from the ballast-adapters, so there are none of Lights of
America's troublesome contacts here. These are 34 and 45 watt units.
The package of the 34 watt unit claims a light output of 2400 lumens and
equivalence to a 150 watt incandescent lightbulb. The 45 watt one claims
a light output of 3100 lumens and equivalence to a 200 watt lightbulb.
These lamps are impressive, so I don't think that Lights of America needs to exaggerate these claims. However, I believe they do anyway. I have tested the 45 watt unit, and determined the light output to be about 2700 lumens. This is slightly less than the light output of a standard 150 watt lightbulb. If extrapolation tells the truth, then the 34 watt unit would put out about 2100 lumens - a little less than halfway from a standard 100 watt lightbulb to a 150 watt one.
These 34 and 45 watt lamps do not have the very warm color of the 14, 18, and 27 watt "Q-Lites", but have a more typical compact fluorescent lamp color around 2800 Kelvin and are very slightly more-pink/less-yellow than an incandescent lamp.
UPDATE 2/29/2000 - My 45 watt one had an early failure! After operating for about 3 hours base-down in an unenclosed fixture which only minimally obstructed the bottom ventillation holes in the ballast section at the base of the bulb, this thing failed with a popping sound. It flickered briefly a few times during that 3 hours. All previous operation amounted to less than 10 hours for a total life of very roughly 12 hours.
I recently got one of the Lights of America 25 watt Twister bulbs, claimed to have light output equivalent to that of a 100 watt standard incandescent. There are two lower wattage Twister units, I believe 18 and 14 watts, with claimed equivalence to 75 and 60 watts standard incandescents respectively.
These bulbs are attractive, truly compact units that slightly resemble swirled ice cream cones. The 25 watt one is approx. 45 mm (approx. 1.75 inches) longer than a standard (A19) lightbulb and no wider than such a standard bulb, so these will fit in most places that regular lightbulbs fit.
According to my tests, the light output of the 25 watt one is about 1375 lumens, or about 80 percent of that of a standard 100 watt 750 hour 120 volt lightbulb. It is slightly dimmer than Philips and Sylvania 23 watt units. The color is a very warm incandescent-looking color of about 2700 Kelvin or slightly less - slightly warmer than most standard lightbulbs of 40-100 watts.
UPDATE 9/5/2000 - On 9/4, 188 days later and after an estimated 400 operating hours, a connection in the above Twister failed. It refuses to work - glows dimly on one end of the tubing and flickers with a sparking appearance when tapped. Tapping and pressing on it the right way has restored it for now. The problem is definitely inside the Twister since other bulbs worked fine in the same socket while the Twister only glowed dimly in one end.
UPDATE 9/30/2000 - this bulb completely failed on 9/20 after an additional estimated 20 operating hours. One end of the tubing showed the dark discoloration typical of end-of-life.
General Electric now sells similar bulbs, and so do others. In mid-July 2001 I bought a 2-pack of 25 watt General Electric ones made in China and having a 6000 hour rated average life expectancy. They were claimed to be replacements for 100 watt regular light bulbs, but they did look a little dimmer than 100 watt incandescents to me when I compared them side-by-side. I never did any attempted lumen light output measurements before they conked out.
UPDATE 8/4/2001 - Testing was mainly on just one of them from mid July to 8/2 2001, amounting to (VERY ROUGHLY ESTIMATED) 200 operating hours, averaging a low but low-side-of forseeably normal figure of 15 minutes per start. The unit under test failed on 8/2/2001. My experience is that compact fluorescents should normally last a couple thousand or more hours even with such severe starting duty as averaging a start per 15 minutes of run time.
Update 8/26/2001 - the other one failed on 8/23/2001. This was about three weeks of use no more than a few hours per evening, a few starts per evening, and maybe 3-4 days per week. I don't have a more accurate log than this, but the total run time had to be under 100 hours, maybe even under 50 hours, and the number of starts was around 100. I thought General Electric would rather have their name on something better than this batch of duds!
I have yet to test these myself, but I imagine that the R40 has a diffuse floodlight beam not quite as good as that of incandescent floods. But it is probably not far short of incandescent and halogen floods of similar light output (the 20 watt one produces about as much light as 65-75 watt floods). The 20 watt R40 is probably a very useful floodlight where there is room in the fixture for the 5 inch diameter reflector. I would allow at least 1/4 inch of space around the reflector's edges to assist dissipating the heat.
I have the feeling that the R30 reflector is a much more compromised design.
F13TT/27K (this is 2700 Kelvin.)
PLC*15/28/28 (The second-last number here is wattage, the last means 2800 K)
F40T12/D835 (The D835 means 3500 Kelvin)
Now, here is what these numbers mean to you.
Numbers from 27 to 30 or 2700 to 3000 represent generally incandescent colors. Sometimes, the color may be a bit less yellow and slightly more pink/purple, but it is a basically incandescent color.
Numbers around 35 or 3500 represent a whitish incandescent color, similar to that of projector bulbs, some photographic lamps, and the whitest halogen lamps. Unless you are using enough of these bulbs to make your home as bright as a classroom, the color may seem slightly greenish or slightly generally "off". If you have a lot of this light, then this color is generally pleasing.
Numbers around 41 represent colors generally like that of "cool white" fluorescent lamps. A few of these are also very slightly on the purple side. They generally don't make colors look dull like standard cool whites do, since they have a different spectrum from use of different phosphors. However, unless you have classroom-bright light levels, this color has a dreary gray effect.
Avoid buying any "Abco" brand bulbs unless the color code is visible and desirable. I have seen some with the 41 color code marketed as "warm white".
There is also a 50 or 5000 color. It is an icy cold pure white that sometimes looks slightly bluish. Like the 41 color, they can cause a dreary gray effect unless you have very bright lighting levels - despite this being a close approximation to noontime tropical sunlight!
Beware of the 21 color code that I have seen on a very few Osram brand bulbs. It seems to be a misprinted 41. These bulbs have a very slightly purplish cool-white color.
Please note that these bulbs were often claimed to produce 900 lumens of light, and they actually make more like 820-825 lumens. (even less, 780 lumens, for the more compact double-twin or quad tube.) The 820 lumen figure is about 90-95 percent of the light output of a 60 watt bulb. The lumen claims have largely gotten more realistic in recent years, at least with the GE, Sylvania and Philips brands.
UPDATE 3/18/2001 - I just looked in my Philips catalog, and there are separate figures for initial lumens and design lumens. I believe the latter is for bulbs of average age and condition in average usage. Those numbers for 13 watt ones are around 715-735 lumens. That is a little more than halfway from a regular 40 watt incandescent to a 60 watt one in light output, or about the same as many long-life 60 watt incandescents.
If these bulbs are operated base-down and subjected to shock or vibration, the mercury in these bulbs gets excessively hot until it evaporates and recondenses in cooler parts of the bulb. The bulb may temporarily lose about 30 percent of its light output for a few minutes. These bulbs may also overheat and get a bit dim if operated in fixtures subject to excessive heat buildup.
My experience with this involves bulbs made more than 8 years ago, and there is a possibility that some newer ones may not be as bad with this.
The ballasts for these bulbs are usually "magnetic" or "iron" ones, many of which are cheaply made and make a buzzing or even a cricketlike squeaky-buzzing sound. If possible, test the ballast or fixture for buzzing sounds. If there is any doubt, it is possible that the ballast will sound louder at home - beware!
Copyright (C) 1996 Donald L. Klipstein.
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