Short-lived 9W CFLs on photocell
#1
Short-lived 9W CFLs on photocell
I bought (10) magnetic-ballasted 9W CFL outdoor wall fixtures from Lights of America in 2001, then in 2005 bought (6) more of same, except electronically ballasted. Summer of '07 I designed an aluminum "can" so as to install the (16) lights under the soffit around my house, controlled by an Intermatic 3-wire photocell rated (8)Amps Ballasted Load.
In a year and a half, nearly all the original bulbs have burned out, (2) magnetically ballasted fixtures have overheated(plastic melted adjacent to the ballast) and different branded bulbs (Sylvania & GE) are failing early as well. I don't think ambient temp. is a factor, as the failures seem to be occurring equally during hot and cold season. The orig. bulbs are 2700K but I tried a few 7800K Sylvania bulbs but they would only glow at the base until you touched them, then they would light up.
A month ago I sent e-mails to Intermatic, LOA, Sylvania and GE, and only Sylvania responded by saying "only use bulbs specified by the manufacturer"....had never heard of LOA...
real helpfull. My next step is to try an isolation relay, even tho I'm told a (3) wire photocell is correct type for "all ballasted loads".
Any suggestions???
In a year and a half, nearly all the original bulbs have burned out, (2) magnetically ballasted fixtures have overheated(plastic melted adjacent to the ballast) and different branded bulbs (Sylvania & GE) are failing early as well. I don't think ambient temp. is a factor, as the failures seem to be occurring equally during hot and cold season. The orig. bulbs are 2700K but I tried a few 7800K Sylvania bulbs but they would only glow at the base until you touched them, then they would light up.
A month ago I sent e-mails to Intermatic, LOA, Sylvania and GE, and only Sylvania responded by saying "only use bulbs specified by the manufacturer"....had never heard of LOA...
real helpfull. My next step is to try an isolation relay, even tho I'm told a (3) wire photocell is correct type for "all ballasted loads".
Any suggestions???
#2
Hi rstripe, I've been reading all posts related to CFL's and find many comments for which I can't find bulbs. A recent thread suggested they should get bulbs rated for inverted use, as in cans. I haven't had a chance to visit the big box and read all of the package labels, but I will. The issue for me is all of the do's and don'ts, there just doesn't seem to be a master list.
Obviously something is going on with yours and it would be nice to know what. You can expect some questions on your "can" design, so I'll get you started. There are well ventilated cans and non-vented as in IC rated. The IC rated I believe are double wall and designed to vent or dissipated heat to somewhere other than the space above. If yours are sealed, perhaps they lack the proper cooling capability.
Beyond that, I'll just wait to see what others have to say.
HH
Bud
Obviously something is going on with yours and it would be nice to know what. You can expect some questions on your "can" design, so I'll get you started. There are well ventilated cans and non-vented as in IC rated. The IC rated I believe are double wall and designed to vent or dissipated heat to somewhere other than the space above. If yours are sealed, perhaps they lack the proper cooling capability.
Beyond that, I'll just wait to see what others have to say.
HH
Bud
#3
2 things I would check:
1. are the lamps listed as suitable for use with a photocell. I understand this has been a problem in some although I do not believe that would cause the burned plastic problem. Maybe a life expectancy problem though.
2. are the lamps listed for universal position mounting? Mant early cfl's could not be mounted base up and were short lived due to the heat the ballast was subjected to due to the position.
If you cannot find a listing for mounting position on the packaging, I would contact the manuf. and ask that specific question.
1. are the lamps listed as suitable for use with a photocell. I understand this has been a problem in some although I do not believe that would cause the burned plastic problem. Maybe a life expectancy problem though.
2. are the lamps listed for universal position mounting? Mant early cfl's could not be mounted base up and were short lived due to the heat the ballast was subjected to due to the position.
If you cannot find a listing for mounting position on the packaging, I would contact the manuf. and ask that specific question.
#4
more info:
About photocell use---The instructions say to not use photocell control....but I believe that's so they don't have to go into detail on which type is and is not acceptable. LOA sells other CFL designs which have built-in photo-control so I think as long as it is a 3-wire type balast-rated control I should be OK. But, as I said, I'll try an isolation relay next.
As to the "cans" & orientation--- The fixtures measure about 12"L x 8"W x 4"D. It 's an enclosed plastic box with one face being the lens and the opposite face having a small hole for the wire leads. It is designed to be surface mounted on a wall. The arrow indicates mounting with the bulb "base up".
The bulb is a "u" shape with 2 pins. (LOA said it really does not matter how they are oriented, when I asked them in 2000)
Instead of surface mounting directly to the soffit, the can, which is open bottom and top, allows the fixture to recess into the soffit for a more pleasing appearance.
The soffit has many vents and, being somewhat lower than the attic floor, the soffit temps should not be more than 5-10 degrees hotter than outdoor temps in summer.....anyway, the bulbs are failing irrespective of seasonal temps.
Hope this add. info helps. Thanks.
As to the "cans" & orientation--- The fixtures measure about 12"L x 8"W x 4"D. It 's an enclosed plastic box with one face being the lens and the opposite face having a small hole for the wire leads. It is designed to be surface mounted on a wall. The arrow indicates mounting with the bulb "base up".
The bulb is a "u" shape with 2 pins. (LOA said it really does not matter how they are oriented, when I asked them in 2000)
Instead of surface mounting directly to the soffit, the can, which is open bottom and top, allows the fixture to recess into the soffit for a more pleasing appearance.
The soffit has many vents and, being somewhat lower than the attic floor, the soffit temps should not be more than 5-10 degrees hotter than outdoor temps in summer.....anyway, the bulbs are failing irrespective of seasonal temps.
Hope this add. info helps. Thanks.
#5
so, the lamps specifically say not to use photocell control. There is usally a reason for that which is, you aren't supposed to use those on photo-controls, of any kind.
I don't know who LOA is but they lied in 2000. Back then, most lamps were for base down or horizontal mounting. A lamp needs to be rated for the position. Believe it or not, even the standard 60 and 100 wat incandescents sold everywhere are rated for position.
So, with that, either packaging or manufacturer is the only reliable recommendation for position.
It doesn't make any difference what the fixture states, it is what the lamp is listed for that is important.
I don't know who LOA is but they lied in 2000. Back then, most lamps were for base down or horizontal mounting. A lamp needs to be rated for the position. Believe it or not, even the standard 60 and 100 wat incandescents sold everywhere are rated for position.
So, with that, either packaging or manufacturer is the only reliable recommendation for position.
It doesn't make any difference what the fixture states, it is what the lamp is listed for that is important.
#6
LOA is Lights of America which I believe is a Chinese or Korean company. I do know that generally speaking they have lamps of lesser quality.
Concerning the U shaped fluorescents...I installed a couple of enclosed outdoors fixtures in my parent's home back in the late '80s or early '90s. Neither lasted a year and bulb replacement was not the answer. These had regular switches and one was used only rarely.
My outside lamps are all semi-enclosed lanterns, open on the bottom. I've been using CFLs for several years now and last month I looked at one of the bulbs and it had been in place about two years. These are on a three-wire photocell and so average about 12 hours a day 364 days a year. For what it's worth these are Feit lamps and the fixtures require the bulb to be base up. I get them for a buck a piece at the local hardware store with an electrical utility coupon. It's not even my utility.
Concerning the U shaped fluorescents...I installed a couple of enclosed outdoors fixtures in my parent's home back in the late '80s or early '90s. Neither lasted a year and bulb replacement was not the answer. These had regular switches and one was used only rarely.
My outside lamps are all semi-enclosed lanterns, open on the bottom. I've been using CFLs for several years now and last month I looked at one of the bulbs and it had been in place about two years. These are on a three-wire photocell and so average about 12 hours a day 364 days a year. For what it's worth these are Feit lamps and the fixtures require the bulb to be base up. I get them for a buck a piece at the local hardware store with an electrical utility coupon. It's not even my utility.

#7
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All photocells are listed for the type of laod that can be connectrd to them, ie, tugsten, or magnetic ballast. I don't think electronic ballasts are an issue. I do know that if you can decipher the hyroglyphs(?) on the lamp package, it will show you the proper burn position. It's indicated by a circle with arrows pointing out-ward, either vertical, horizontal or at 45 degrees.
Lamp life is rated by X number of lights burning 24/7 and x number burning @ 3 hr. intervals. When 70 percent of the bulbs are gone, that is end of life. Then they arverage the two findigs for lamp life.
Also, since light bulbs are the lightest box in the recieving dept., they get thrown thw farthest.
I hope this info is helpful.
All CFL's are made in China or Korea !!!
Lamp life is rated by X number of lights burning 24/7 and x number burning @ 3 hr. intervals. When 70 percent of the bulbs are gone, that is end of life. Then they arverage the two findigs for lamp life.
Also, since light bulbs are the lightest box in the recieving dept., they get thrown thw farthest.
I hope this info is helpful.
All CFL's are made in China or Korea !!!
#8
I bought (10) magnetic-ballasted 9W CFL outdoor wall fixtures from Lights of America in 2001, then in 2005 bought (6) more of same, except electronically ballasted. Summer of '07 I designed an aluminum "can" so as to install the (16) lights under the soffit around my house, controlled by an Intermatic 3-wire photocell rated (8)Amps Ballasted Load.
I wrote down the underline there let me ask you this question is the luminaire you brought is a standard wall pack ?
If so and you make a box can so you can make them hidden in the soffet ?
If so that the case the heat trap can useally kill them unless they are specifed for that useage.
and AFAIK some wallpacks are not designed to work in ceiling appactions due the heat issue from the ballast or lamp or both.
If it was mine set up I will just buy a good commercal grade real recessed cans with hardwired CFL ballast { not the screw in type } that useally work far much better and have no issue with it.
Merci,Marc
#9
as french said as well, many CFL's are not listed to use in an enclosed fixture. If this is effectivey an enclosed fixture and the lams are not rated for such, what you are experiencing can be the result.
rmebob
All photocells are listed for the type of laod that can be connectrd to them, ie, tugsten, or magnetic ballast. I don't think electronic ballasts are an issue
All photocells are listed for the type of laod that can be connectrd to them, ie, tugsten, or magnetic ballast. I don't think electronic ballasts are an issue
#10
Marc, to answer your question, yes these are what the LOA calls "Wall Pack".....the magnetic ballast or electronic pc board occupies a very small space within a plastic box of the dimensions previously indicated.....the can serves only as a spacer or sleeve to support the fixture in the soffit. The wall pack itself has no ventilating holes, so as long as it is not placed in a hot environment, say more than 110 degrees, I should be OK? And after all, they are made for exterior use, therefore, seasonal temp. extremes.
The installation places the bulb in a horizontal position rather than base up so possibly more heat can stay close to the bulb compared to a vertical orientation....The only way to introduce ventillation would be to drill a series of say one-eighth inch holes in the lens, then the reflector, then the back of the flat pack to allow air to circulate.
As you say, in hindsight, I would have been better off using a commercial design, but I am already committed to this particular design so I'll try what modifications I can to maximize the bulb life
Thanks all for your input!
The installation places the bulb in a horizontal position rather than base up so possibly more heat can stay close to the bulb compared to a vertical orientation....The only way to introduce ventillation would be to drill a series of say one-eighth inch holes in the lens, then the reflector, then the back of the flat pack to allow air to circulate.
As you say, in hindsight, I would have been better off using a commercial design, but I am already committed to this particular design so I'll try what modifications I can to maximize the bulb life
Thanks all for your input!
#11
Let me guess the Model #9209 If that the case if correct model .,, some of them are listed for both wall / ceiling (soffet) useage.
I will double check the instructions to verify to confirmed to see if they can run in ceiling useage without any issue with it.
( I am not a super strong fan with LOA but they have pretty good selections they are fine for resdentail useage but commercal useage that pretty much out of the picture.,,, )
Normally for wallpack I used well knowen brandnames what many electricians been using for many years and have no issue with it.
I know they are not cheap in most case but it really worth it.
However I know pretty good percentage of LOA with electronic ballast for the CF some of them just can't take the surge that what useally fried them.
If ya have more question just holler one of us will able help ya more with the details ya need to know.
Merci,Marc
I will double check the instructions to verify to confirmed to see if they can run in ceiling useage without any issue with it.
( I am not a super strong fan with LOA but they have pretty good selections they are fine for resdentail useage but commercal useage that pretty much out of the picture.,,, )
Normally for wallpack I used well knowen brandnames what many electricians been using for many years and have no issue with it.
I know they are not cheap in most case but it really worth it.
However I know pretty good percentage of LOA with electronic ballast for the CF some of them just can't take the surge that what useally fried them.
If ya have more question just holler one of us will able help ya more with the details ya need to know.
Merci,Marc
#12
Marc, that is the correct model number. I did not know that other companies make this "flat pack" design. I wonder if the same size and wattage is available in a more reliable brand.
It is very inconvenient to service these lights due to the location, so I would gladly pay more for a luminaire that would give me the typical 10,000 hours advertised for most CFLs.
It is very inconvenient to service these lights due to the location, so I would gladly pay more for a luminaire that would give me the typical 10,000 hours advertised for most CFLs.
#13
Just give me a day or two I will come up with something it will work in your favour and also have more light to boot as well.
{ if ya can give me your rough opening deminson then I will come up with something it will work to your way oh yeah the mounting height as well from the ground level to the location of the luminaire { that way I dont get one that crank out too much light }
Merci,Marc
Just a afterthought here to get 10,000 hours life of the CF they have to be burning at least 3 hours or more if ya running at least 8 or more hours it may go more longer but not much more something like 12,000 maybe 14,000 hours the most unless it on 24/7
{ if ya can give me your rough opening deminson then I will come up with something it will work to your way oh yeah the mounting height as well from the ground level to the location of the luminaire { that way I dont get one that crank out too much light }
Merci,Marc
Just a afterthought here to get 10,000 hours life of the CF they have to be burning at least 3 hours or more if ya running at least 8 or more hours it may go more longer but not much more something like 12,000 maybe 14,000 hours the most unless it on 24/7
Last edited by french277V; 12-21-08 at 01:19 AM. Reason: add a afterthought note
#14
Marc,
The actual dimension of the 9209 is 9.5" long x 6.75" wide
x 3.25" deep, including the curved lens, but the body of the luminaire suspended above the can is only 1.7" deep, so the lens protrudes below the top rim of the can. Rough opening in the soffit is 9.75" x 7.0". The can depth is about 4".
Height above ground is only 7 feet, and by placing these lights about 20 feet apart, 9W CFL is the perfect amount of illumination, using 2700K CRI bulbs. By the way, does a higher or lower CRI make any difference on bulb longevity? I do not mind using a higher (cooler?) CRI, if those bulbs last longer, but the really high CRI looks too "industrial" like mercury vapor lights.
Anyway, I will check back in a few days to see if you have any information, and please know that I appreciate your efforts to help all of us "do it yourselfers" here!
The actual dimension of the 9209 is 9.5" long x 6.75" wide
x 3.25" deep, including the curved lens, but the body of the luminaire suspended above the can is only 1.7" deep, so the lens protrudes below the top rim of the can. Rough opening in the soffit is 9.75" x 7.0". The can depth is about 4".
Height above ground is only 7 feet, and by placing these lights about 20 feet apart, 9W CFL is the perfect amount of illumination, using 2700K CRI bulbs. By the way, does a higher or lower CRI make any difference on bulb longevity? I do not mind using a higher (cooler?) CRI, if those bulbs last longer, but the really high CRI looks too "industrial" like mercury vapor lights.
Anyway, I will check back in a few days to see if you have any information, and please know that I appreciate your efforts to help all of us "do it yourselfers" here!
#15
Another one went out last nite...a Sylvania bulb, replaced only (2) months ago...blackened area at both bases of bulb...magnetic balast appears OK (no burnt smell). I just don't think failures are temperature related...Wintertime, summertime, they fail at the same rate.
#16
Ok ., how often it will come on like how many hours per nite it will lit up or just come on for few minutes it will make the diffrence there { is this luminaire is switched controlled or photocell controlled ?}
Right now I can't find a suitable repacement luminarie as you qouted the size of the box but I am still looking unforetally I have to put it on hold tempory due I am in Paris France at the moment.
Merci,Marc
#17
Marc,
As I indicated on a previous post, these lights are controlled by a photocell; on at dusk, off at dawn.
I hope you are enjoying your visit to Paris, and I will hopefully communucate with you on your return.
Richard
As I indicated on a previous post, these lights are controlled by a photocell; on at dusk, off at dawn.
I hope you are enjoying your visit to Paris, and I will hopefully communucate with you on your return.
Richard
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Here's what I was told:
A flourescent bulb (compact, 4ft, whatever) needs a certain amount of voltage to "turn on". After it's on, a much smaller amount of voltage is needed to keep the glowing gas in the tube "excited" to keep it "on". Thus a ballast which, among other uses, senses when it is "on" and then reduces the voltage. (A CFL has a electronic ballast in the base of each bulb)
Try a CFL on your stove/range hood light. Same brightness if it's on 'lo' or 'hi'. It's either on or off. No inbetween. The reason you can't use a dimmer on them.
When a dusk-to-dawn lamp senses light or darkness, current slowly increases in the ballast until the bulb turns on. When the light flickers (can't decide between day and night) it is EXTREMELY bad news for an electronic ballast. Imagine those electrons slamin' back and forth not knowing which way to go. Poor little things. Finally they explode! Burning out the ballast.
CFL's don't like dusk-to-dawn fixtures.
But keep using CFL's. My stock keeps going up.
SteveS
A flourescent bulb (compact, 4ft, whatever) needs a certain amount of voltage to "turn on". After it's on, a much smaller amount of voltage is needed to keep the glowing gas in the tube "excited" to keep it "on". Thus a ballast which, among other uses, senses when it is "on" and then reduces the voltage. (A CFL has a electronic ballast in the base of each bulb)
Try a CFL on your stove/range hood light. Same brightness if it's on 'lo' or 'hi'. It's either on or off. No inbetween. The reason you can't use a dimmer on them.
When a dusk-to-dawn lamp senses light or darkness, current slowly increases in the ballast until the bulb turns on. When the light flickers (can't decide between day and night) it is EXTREMELY bad news for an electronic ballast. Imagine those electrons slamin' back and forth not knowing which way to go. Poor little things. Finally they explode! Burning out the ballast.
CFL's don't like dusk-to-dawn fixtures.
But keep using CFL's. My stock keeps going up.
SteveS
#19
I tried to tell him that many posts ago and was ignored but hey, maybe I should start looking into the same stock your riding.
What OP needs to do, if he is going to use a photocell is use the PC to control a contactor so the power to the actual lamp is either off or on. No leakage voltage.
What OP needs to do, if he is going to use a photocell is use the PC to control a contactor so the power to the actual lamp is either off or on. No leakage voltage.
#20
nap,
I was once told that if you use a three-wire photocell and it says it is rated for "incandescent AND ballasted loads, it is essentially a relay. I have seen the type of PC you're talking about, used with incandescent bulbs---they slowly, flickeringly, increase in intensity as it gets darker outside. But, again, I don't have that type PC. At this point, however, the easiest thing to do would be to install an isolation relay/contactor to see if it makes any difference....But I really think my problem is inferior quality fixtures. This PC also operates (3) 7W CF fixtures made by Regent brand, and they are still burning after a year and a half.
It's the LOA luminaires that are short-lived.
I was once told that if you use a three-wire photocell and it says it is rated for "incandescent AND ballasted loads, it is essentially a relay. I have seen the type of PC you're talking about, used with incandescent bulbs---they slowly, flickeringly, increase in intensity as it gets darker outside. But, again, I don't have that type PC. At this point, however, the easiest thing to do would be to install an isolation relay/contactor to see if it makes any difference....But I really think my problem is inferior quality fixtures. This PC also operates (3) 7W CF fixtures made by Regent brand, and they are still burning after a year and a half.
It's the LOA luminaires that are short-lived.
#21
unless the lamp itself states it is rated to use PC's, it doesn;t matter what type of PC you use. The manuf. is not listing them for that use and there is generally a reason for it.
It may be improperly listed but the fact remains.
the first thing I would do is eliminate this possibility. If you try to dance with too many partners, you will never know which one made your toes sore when you wake up the next day with sore toes.
It may be improperly listed but the fact remains.
the first thing I would do is eliminate this possibility. If you try to dance with too many partners, you will never know which one made your toes sore when you wake up the next day with sore toes.
#22
Last week, I installed an isolation relay between the photocell and CFL's in my "process of elimination"
Today, after a second e-mail sent to the photocell manufacturer (Intermatic), they answered me with a short, sweet reply: "Our photo controls are rated for CFL's. No isolation relay is needed" OK, we'll see.
I continue to learn the peculiar nature of CFL's ---I'm testing a new LOA fixture with electronic ballast, works fine with it's included bulb, but when I substitute two different brand bulbs, they only glow at the base, unless you touch them with a finger, then they turn full on! It did this a dozen times in a row. I was about to return them to the store, but first I tried them on one of my older magnetically ballasted fixtures, and Voila! works fine! Every time!
Strange beasts, these CFL's....
Perhaps I'll hear back from Marc, shortly.
Today, after a second e-mail sent to the photocell manufacturer (Intermatic), they answered me with a short, sweet reply: "Our photo controls are rated for CFL's. No isolation relay is needed" OK, we'll see.
I continue to learn the peculiar nature of CFL's ---I'm testing a new LOA fixture with electronic ballast, works fine with it's included bulb, but when I substitute two different brand bulbs, they only glow at the base, unless you touch them with a finger, then they turn full on! It did this a dozen times in a row. I was about to return them to the store, but first I tried them on one of my older magnetically ballasted fixtures, and Voila! works fine! Every time!
Strange beasts, these CFL's....
Perhaps I'll hear back from Marc, shortly.
#24
Rstripe.,
I talked to my French sparkys and we swap the notes about the situation unforeally we do get LOA in France!
One of them suggest a trick is get the earth { grounding } conductor and tie to the main ground wire in the junction box and string it along the bulb sometime it will help to start up the luminaire bulb.
I wish make a drawing how to do this but not good on this yet and yeah I am still in France { long term stay }
Merci,Marc
I talked to my French sparkys and we swap the notes about the situation unforeally we do get LOA in France!

One of them suggest a trick is get the earth { grounding } conductor and tie to the main ground wire in the junction box and string it along the bulb sometime it will help to start up the luminaire bulb.
I wish make a drawing how to do this but not good on this yet and yeah I am still in France { long term stay }
Merci,Marc
#25
Hello Marc,
good to hear from you again...yes, maybe the proximity of a ground wire would affect the reactance in the bulb.....
But for now, I'm going to wait a few months to see if my isolation relay might be the answer.
I would still be curious to know if you become aware of a commercial-grade "Flat-Pack" type luminaire of similar size.
Thank you, again.
good to hear from you again...yes, maybe the proximity of a ground wire would affect the reactance in the bulb.....
But for now, I'm going to wait a few months to see if my isolation relay might be the answer.
I would still be curious to know if you become aware of a commercial-grade "Flat-Pack" type luminaire of similar size.
Thank you, again.
#26
nap, thanks for the pic of Vermiculite in the other forum, and for this subject, I believe you are proving correct.....I still have had no CFL failures since installing the isolation relay....
so much for the theory that a 3-wire photocell is a dry contact relay.....
so much for the theory that a 3-wire photocell is a dry contact relay.....
#27
glad to hear it, so far, has solved your problem.
did you figure out how to stuff all that vermiculite back into the wall? It is a bit of a surprise when it just keeps pouring out, and pouring out, and......
did you figure out how to stuff all that vermiculite back into the wall? It is a bit of a surprise when it just keeps pouring out, and pouring out, and......
#28
Hello Marc,
good to hear from you again...yes, maybe the proximity of a ground wire would affect the reactance in the bulb.....
But for now, I'm going to wait a few months to see if my isolation relay might be the answer.
I would still be curious to know if you become aware of a commercial-grade "Flat-Pack" type luminaire of similar size.
Thank you, again.
good to hear from you again...yes, maybe the proximity of a ground wire would affect the reactance in the bulb.....
But for now, I'm going to wait a few months to see if my isolation relay might be the answer.
I would still be curious to know if you become aware of a commercial-grade "Flat-Pack" type luminaire of similar size.
Thank you, again.
One other manufacter did make simuair item as you descrbing and they no longer make that one and still looking for one for ya.
Merci,Marc
#29
Thanks, Marc, every week that goes by without further failures, leads me to believe the isolation relay is my answer...
I'm thinking that the manufacturer (Intermatic) rated their photocell for CFL's generically, without evaluating the wide range of wattages available; it may be that with very low wattages (mine are 9W), thereby requiring very little current, the leakage current from a PC in the "OFF" condition could cause problems. Who knows?
I'm thinking that the manufacturer (Intermatic) rated their photocell for CFL's generically, without evaluating the wide range of wattages available; it may be that with very low wattages (mine are 9W), thereby requiring very little current, the leakage current from a PC in the "OFF" condition could cause problems. Who knows?