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Lighting

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Started 2 years ago by ely
Latest reply from swanning_it

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ely
Member

Hi all,

I've checked out the old issues of ReNew, but nothing since Jan 08 - so I figure there might be more up to date info out there.

We're building a house and are at the choosing lighting stage.

The builder and electrician were trying to talk me into getting Halogens for downlights in a hall that will be illuminating a rammed earth wall - they say halogens give a nice yellow light and that fluoro and LED give a blue light that won't look nice on the earth wall.

Reading a bit about Halogens makes me not want them at all. I figure there must be some options in different colours for LED and fluoros by now?

I see some prices for LEDs at Todae shop - bit expensive. But I also see that they are making now LEDs that fit standard light fittings. Should I go with standard fluoro lights and hope to be able to afford replacement LEDs in the future?

Any tips on educating myself more in lighting (without too much tecnnicalities?).

Thanks,

Ely

Posted Saturday 20 Feb 2010 @ 11:42:58 am from IP #
dymonite69
Member

Good colour rendition and colour temperature is based on the reference point of how something would like under 'natural' light source ie. sunlight (almost ideal black body radiator). Incandescent and halogen lamps come closest to mimicking this.

All other lamps are not able to absolutely match this. They alway look a little less 'warm' than standard lights e.g. 'cold' looking fluoros of the past. But they are getting better e.g. triphos tubes, 'warm' CFLs. LEDs also can come in 'warmer' colour but at the cost of light output.

Basically objects will seem to take on a slightly different colour when illuminated at night by these alternatives.

It really comes down to a matter of taste and preference.

LEDs are quite trendy nowadays but you still quite a few of them to provide adequate lighting (expensive). They are also more directional (unlike standard bulbs) so it is trickier to provide good general lighting. You will need an alternative lighting plan to get the same effect with more point sources to achieve the same effect. If you just exchanged the halogens with LED drop ins then you will find the lighting pattern will alter even if the lumens output is maintained.

Posted Saturday 20 Feb 2010 @ 1:25:54 pm from IP #
ghostgum
Member

For downlights, I'd probably go for warm white LEDs at this stage, but you are looking at $200 per fitting. The Hotbeam CeeLux lights are one example.

Using a PLC fluoro downlight will also work, or an incandescent downlight with a compact fluoro in it, but most of these are vented, so you lose heat up them during winter. I've got some that aren't vented, but the frosted glass at the ceiling throws light sideways and make it a bit glary. You can get warm white fluoros (colour temperature 2700 or 3000), but as dymonite says, colours will look a little different to incandescent.

If you are trying to light a wall, then I'm not sure that downlights are the best. Can you do something with wall sconce lights, or with long T5 fluoros mounted on the wall behind a board so it lights up and down?

Posted Saturday 20 Feb 2010 @ 8:46:59 pm from IP #
Novi Grad
Member

During my recent renovations, I installed a combination of CFL (compact fluorescent lights), halogen and LED lights. The (4) halogen lights are in single pendant fittings above the dining table (dimmable), the CFL's are throughout the house (and yes, they are vented but this is minimal compared to the old incandescent globe downlights and also less than the halogen downlights they replaced and they are much cooler and need no transformer)and are of the warm-white variety (2700 Kelvin), 14 to 25 Watts. I also have CFL's in a wall-wash situation using GU10 mounting in conventional (halogen) downlight fittings. This is less than successful, particularly for colour. Lastly we have LED lighting strips (warm white, approx 2500 - 3000 Kelvin, 60 cm long) in our kitchen display cabinet and on either side of the bathroom mirrors. This is very successful and though not cheap, the effect is excellent. My experience was that new products were coming on the market all the time and the longer I waited, the better the choices. The 14 or 25W CFL's using the normal screw mount in a Telbix Super Mini or CLA downlight fitting with chrome reflectors was the best solution to general lighting. The LED lighting strips were the best for low-energy "wash" lighting though the long T5 Fluoros would be a lot cheaper.

Posted Saturday 20 Feb 2010 @ 10:25:59 pm from IP #
LanceTurner
Key Master

I have to say I don't know why anyone would be using halogens nowadays, they are just the most inefficient things around. There are heaps of LED options now, you just have to think outside Australia if you want to get them at realistic prices. We just did a retrofit removing 8 x 50 watt GU10 fittings. Opened up the ceiling holes a bit and put in ES27 based downlight can fittings then fitted ZetaLux bulbs from Earthled, the end result was much better light and a reduction in energy use on a huge scale - from 400 watts down to 48 in total. More in the next ReNew on this retrofit...

Despite the fact that the Zetalux is only rated at around 350 lumens and a 50 watt halogen is around 3 times that, because the LED bulbs have a wide dispersion angle they light the room directly rather than from light reflecting off the floor, so you end up with better lighting with the LEDs (unless you have white shiny floor tiles : )

There are so many LED options out there, there's just no reason to light a house with anything else. Ciolour temperature isn't an issue, you can get any colour you want, from very cool 6500K or cooler, through to very warm, 2500K, and pretty much anything in between. My whole house now (and a rental at that) is pretty much totally LED lit, the only fluoros to replace are the 40 watt tubes in the kitchen, which I'll get to eventually...

A list of both Australian and overseas downlight options is below - there's plenty more out there. Also check out ebay, there's lots of good (and bad) LED bulbs on there now. The things to look for in any LED bulb are:

1) Quality LEDs, like Cree, Nichia, Taiwan Edison etc.
2) High efficacy - any LED bulbs should be around 50 lumens per watt or better nowadays.
2) Good heatsinking design. You need surface area, not just lots of metal. Also, heatsink finish is important, there's lots of chromed bulbs out there - they run hot, chrome is a bad heat emitter.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220424537450&ssPageName=STRK:MEWAX:IT

http://www.hotbeam.com/cool.light/1lighting-11CLX.cfm

http://www.digilin.com.au/products.asp?name=ICON-816%20LED%20Downlight

http://www.cutter.com.au/proddetail.php?prod=cut796

http://www.superled.com.au/FWS/modules/estore/public/fes_catalog.php?id=3

http://www.todae.com.au/Products/ledlighting/ceelux13wleddownlightfitting/

http://www.neco.com.au/lighting/bright-green-d12-led-downlight-12w

http://www.dowin-australia.com/proshow.asp?id=135

http://www.ledlighting.com.au/9W-LED-Fitting.html

http://www.ledaustralia.com.au/epages/lele4117.sf/en_AU/?ViewAction=View&ObjectID=14893

http://www.earthled.com/

http://www.fobsun.com/en/product_show.asp?P_id=434&ti=

http://alternateenergysolutions.com.au/blog/led-lighting/led-down-lights

http://www.optiled.com/ProductDetail.aspx?id=1ae8b1de-dde2-48da-a59b-cecd78608876&CountryId=819167ab-d169-4c36-aaf1-d53f8ca33cb8

http://www.lighting.philips.com/in_en/global_sites/led_lighting/products/master_led/product_range.php?main=gb_en&parent=1&id=in_en_led_lighting&lang=en

http://www.artandsciencecombined.com/Products.aspx

http://www.spectrumlighting.com.au/energy_efficient_globes.php

http://shop.ata.org.au/cart.php?target=category&category_id=326

Posted Monday 22 Feb 2010 @ 12:30:34 am from IP #
dymonite69
Member

We don't use any downlights in our house. They are also terrible for general lighting. Reflector lamps if needed are best for spot or accent lighting e.g lighting a path, showing art work

Downlights;

a) leave a gap in the insulation (1m2 of uninsulated ceiling loses as much heat as 10m2 of insulated ceiling). Your increased heating requirements will offset your savings in using energy efficient lights.
b) are not an efficient way of lighting a space compared to a pendant. Look closely at a LED surface. It can't project light backwards like a CFL bulb. The distribution of light is as important as the intensity of the light.

Posted Monday 22 Feb 2010 @ 2:07:48 am from IP #
LanceTurner
Key Master

Many people don't have a choice with downlights, they already have them installed and removing them means a lot of holes in the ceiling that have to be fixed, adding considerably to the expense.

LEDs are the best option for getting rid of the halogens. I never recommend downlights for a new installation, but many people still want them as ceilings in modern homes can be quite low, meaning pendant lights are not really an option.

Downlights no longer leave a gap in the insulation, there are insulating covers/cones, like the Tenmat cones and the efficiency matrix downlight mitts, both can have insulation right up to them.

There are LED bulbs in all sorts of sizes and shapes, with different light dispersions (don't assume all of the LEDs are mounted on the same plane), I've tested many and some of the cheap ones are surprisingly good, at least as far as efficiency/light output and dispersion are concerned.

CFLs simply can't compete any longer, and they have the problem of mercury. While it's only a few milligrams per bulb, at a dozen bulbs per house every couple of years, you're talking maybe 50 million bulbs disposed of every year in Oz, assuming everyone converted to CFLs. That's 100 kilograms of mercury, most of it going to landfill, assuming the conservative figure of 2mg per bulb. High quality bulbs can be this low, but the cheap and nasties, which many people buy, have far less accurate mercury dosing and so the figure is bound to be higher.

There are recycling schemes available (more details in the next ReNew) but because of the cost, most people will simply throw them in the bin...

Because of this and other reasons, fluoros are going the way of the dodo, along with incandescants and halogens, and it can't happen soon enough as far as I'm concerned...

Posted Monday 22 Feb 2010 @ 4:02:56 am from IP #
dymonite69
Member

Luminous efficiency of the average LED is not that better than CFL and not a lot different from normal fluoro. We use a combination of both.

Do these cones allow insulation to sit over them?

I take all my CFLs/fluoros to a local light shop for proper disposal/recycling.

LEDs will be the way of the future but not until they are cheaper and the issues of directionality are addressed.

Posted Monday 22 Feb 2010 @ 4:26:10 am from IP #
LanceTurner
Key Master

The average LED is approaching 100 lumens per watt nowadays, even some of my low cost bulbs have LEDs in them around that level. Cree have commercially available LEDs around the 150 lumen per watt class now (I sell some of these, they are just so stupendously bright for their energy use) and they have surpassed the 200 lumen per watt level in the lab, and that's for a nice neutral white of around 4100K, should see them in commercial quantities in around 6 months.

But, it's pretty easy to get a LED bulb or fitting of close to 100 lumens/watt total efficiency now (cool white) or 60-70 L/W in warm white, which is as good as the best CFLs, most are quite a bit less than this. And LEDs get better all the time, CFLs have pretty much reached the limits of their efficiency.

Yes, the cones allow you to put insulation over them, see http://www.downlightcover.com.au/ for an example.

You're lucky to have a light shop that does the recycling, there's none I know of in my area, but always worries me that they are doing it properly. If they are rough with their handling then you end up with broken tubes and the mercury ends up in the environment anyway. You're better off using lamps that don't have this problem in the first place.

I agree they need to be cheaper, but this is only a matter of one of the large lighting companies like Sylvania or Philips getting off their butts and doing a full range of lamps. If I can buy a Zetalux from the US for US$39 from a relatively small mob like Earthled, then large companies should be able to do them for half this.

I know how much Cree LEDs cost, in large quantities they are around $2-$4 each, depending on model/bin. The rest is basic electronics worth a $ or two in mass quantities, basic Cree or similar quality LED based bulbs should cost well under $10 to make if they are made in large volume.

Not sure why you keep harping on directionality, it isn't an issue, just put the LEDs on more than one plane as some manufacturers already do...

In short, in a year or two you are going to see LEDs everywhere, CFLs are a dodo just waiting to die, you can't fight the future

Posted Monday 22 Feb 2010 @ 5:26:36 am from IP #
rsigmund
Member

Cant wait - 'mad as a hatter' is not how I want to end up!

Posted Monday 22 Feb 2010 @ 6:04:16 am from IP #
dymonite69
Member

I presume you are referring to Haitz's law - lumens increase 30% per fitting each year and cost per lumen fall around 20%.

So by 2020 they will be same price as CFLs.

I notice that the Tenmat picture only has 1/4 the insulaton
thickness sitting over the cone.

I have never seen a spherical LED emitter. Have you got a picture.

Posted Monday 22 Feb 2010 @ 6:24:42 am from IP #
Tony C
Member

Hi Ely, it is difficult to choose at the moment because there is a lot of old and false information around.

You mention about illuminating a wall, I am assuming that this wall is a feature for you?

LED lights are available in many types, whether bulbs for fitting into existing bases or conplete units for downlights. You can get different colour and wattage to suit your needs. A lot of spot type led bulbs are a very narrow beam angle which is good for highlighting a feature but can create shadow if you are after whole room lighting.

Have a look at our website http://www.buildingstuff.biz to see some of the downlight fittings with gimble adjust, these are great for highlighting features.

Good luck

Tony

Posted Monday 22 Feb 2010 @ 11:00:39 pm from IP #
ghostgum
Member

dymonite69 wrote "I have never seen a spherical LED emitter."

Why would you want a spherical emitter?
Downlights want 60-180deg spread.
Uplighting the same.
Oyster light fitting the same.
Pendant light with frosted glass diffuser wants close to 360degree, but in reality you probably want more light in some directions than others.
The problem is more than existing light fittings are designed for a spherical emitter. We need to change the light fitting design to suit LED emitters.

LED lights generally use multiple LED chips, and you can arrange these to give an appropriate spread of light.

If you don't like the directionality, then put them behind a diffuser and you end up with a light fitting about the same size as a fluorescent light.

My lighting is currently:
1. Pelmet uplighting using 180W of T5 fluoros for a large room. My plan is to augment this with LED lighting. The LEDs can be dimmed when watching TV.

2. Wall sconce lights with PL-C tube. Longer term I'd like to make an LED module that replaces the CFL. A few LED chips pointing up, a few pointing down, a few out, and one or two on each end.

3. Downlights with 2xPL-C. These have a diffuser glass on the bottom, so no air movement through the light from the room. An LED module could be put behind this with a bit of mechanical work.

4. Downlights using CFL with ES base. I should be able to replace these with LED ES bulbs, after first drilling some holes in the light fitting for ventilation.

5. T5 fluoros for vanity mirror lights. A strip LED light in an aluminium housing would be ideal for this.

Given that I've already got holes in the ceiling for the existing downlights, the problem will be making LED source to suit the existing light fittings.

Posted Monday 22 Feb 2010 @ 11:37:44 pm from IP #
dymonite69
Member

Ghostgum said:

"The problem is more than existing light fittings are designed for a spherical emitter. We need to change the light fitting design to suit LED emitters."

I entirely agree. Of the couple dozen links Lance provided, only about 3 three provided some kind of drop-in alternative for existing fittings. The majority of them were for downlights.

EarthLed had the best range and provided replacements including those for T8 fluoro tubes. Lumen output was equivalent. But I note that they didn't provide an alternative for circular fluoros.

But I can't find an LED lamp that can provide more than 60W equivalent of an incan globe. Currently we have 3x 21W CFL in a tripe pendant fitting over a kitchen bench. This is about 300W equivalent of incandescents.

So there aren't many LEDS that provide equivalent output and beam pattern for existing fittings. And >90% of fittings designed for LEDs are the downlight variety.

If as much effort was placed on design to get the light to where you want as the technical work on lumens/watt then maybe there would be more acceptance of these lights.

As you say good lighting design involves the correct combination of lamp and luminaire.

Posted Tuesday 23 Feb 2010 @ 12:47:39 am from IP #
ghostgum
Member

I forgot to mention another of our lights. 3 pendant lights with frosted glass, each with a 25W CFL, over the kitchen bench. They work really well.

I'm not sure what the best LED equivalent would be. We didn't like the idea of a suspended troffer light (is that what they are called?), although that would have worked. For our pendant lights, a 20cm long heatsink with a few LED chips on the side and lots on the bottom would work. But that shape is not going to fit in many other fittings. With LEDs the reduced heat means you can use plastic instead of glass.

At least with pendant lights you can get good convection cooling of the LED heat sink.

Posted Tuesday 23 Feb 2010 @ 1:16:51 am from IP #
Anonymous
Unregistered

Hi Ely,

Do not use Halogens! They are one of the major causes of household fires. Did you know that a halogen globe can reach temperatures of 500°C and that the temperature that paper will ignite without a flame is 230°C? Scary!

LED Light technology is advancing daily and they are no longer the bluish light of the past. If you buy LED Lights in a Warm White they will complement your earth wall beautifully. LED Lights will save you so much money in the long run as they are extremely energy efficient, long lasting and cool so you can save on air conditioning costs too! led-lamps.net.au has a great energy savings calculator that you can use to calculate the money and energy you will save by installing LED's or replacing your current lights with LED's and it also provides a payback period.

Hope this has been helpful, good luck!

Posted Tuesday 23 Feb 2010 @ 11:02:29 pm from IP #
LanceTurner
Key Master

Useful sites, but the led-lamps.net.au site has some false figures on LED efficiency, no LED is anywhere near 90% at the moment, the best around are close to 50% (Cree R5/S2 bin) and the average is 30-40%. They seem to have used some faulty logic along the lines of: Halogens are 10% efficient. A LED bulb to replace a halogen is usually 10% of the energy use, therefore it must be nearly 10 times as efficient. What they fail to understand is that a 5 watt LED bulb doesn't produce the output of a 50 watt halogen, only 25-35% of the output in fact.

Just be aware that there is a lot of false info around regarding LEDs, most people just don't seem to understand the concepts behind them, or the concepts of efficiency, total light output versus on-axis intensity and various others, all of which adds to a great deal of misleading info out there...

Posted Wednesday 24 Feb 2010 @ 12:06:04 am from IP #
Anonymous
Unregistered

Thank you, Lance, for commenting in regards to our previous post. led-lamps.net.au is a resource and aims to provide accurate information to people who are confused by LED technology. The information published on LED-Lamps has been thoroughly researched, but we will take into account your claims and do so further. We will update any information on our website that was previously misleading. Thank you again for pointing out these possible misconceptions to us, we are currently in discussion with Cree LED manufacturers who will provide us with accurate statistics.

Posted Wednesday 24 Feb 2010 @ 10:36:02 pm from IP #
LanceTurner
Key Master

EnergySaver, sorry, the claims on the site are wrong, the fact that Cree has just produced LEDs in the 200 lumen per watt range proves it, a good commercially available LED (not a finished LED bulb, which has lower efficiency due to driver losses etc) is around 100 lumens per watt. If they were already at 90% efficiency then Cree couldn't have doubled it...

Posted Wednesday 24 Feb 2010 @ 11:53:20 pm from IP #
ghostgum
Member

I agree with Lance. Some information on efficiency of lighting is at
http://en.wikipedia.org/wiki/Luminous_efficacy

The LED Myths page has incorrect facts for Myths 3 and 4, and needs to be fixed.

Posted Thursday 25 Feb 2010 @ 12:02:15 am from IP #
LanceTurner
Key Master

Looks like even my figures are high, a good thing I guess, lots more room for LEDs to improve

Posted Thursday 25 Feb 2010 @ 4:15:18 am from IP #
ely
Member

Hi everyone,

Thanks for so much info and other sites to check out.

I will definitely be avoiding halogens, and I now wonder if I need any downlights at all as our ceilings are high enough for other fittings. They are just pretty trendy at the moment, but I hadn't considered the insulation and the heat problems.

I think I will probably go with fluoros (since we're on a pretty tight budget) and hope that the LED prices come down soon when the fluoros need replacing.

Ely

Posted Thursday 25 Feb 2010 @ 10:32:05 am from IP #
Anonymous
Unregistered

Hi guys,

We just wanted to update you on the fact that we have revised our research and have fixed or removed the incorrect statistics. These misconceptions were due to working confusion during our primary research and the lighting percentage and efficiencies of LED lights have been updated correctly. Thank you again for pointing these mistakes out to us. We appreciate all feedback however great or small.

Ely, good luck with building your home and sorry we hijacked your thread there for a little while We would love to hear what you end up using and how everything turns out!

EnergySaver

Posted Thursday 25 Feb 2010 @ 10:57:54 pm from IP #
Annette
Member

Hi

I have decided against downlighting, to save energy and avoid putting holes in the insulation. Will be installing batten holders and DIY CFL lighting fixtures on bars that fit over these - as a temporary measure so I can change the light styles in future.

I'd like to use LEDs in future.

I have just rewired (it's not finished yet - though most of the cabling has been run). While the ceilings are down, there is full access to the skillion-type roof space.

If I need to lay wiring for future LED additions, this is the time to do it.

Looking at the info site mentioned by EnergySaver, it appears that some special transformer is required to get the best efficiency from LEDs (or is that just down light LEDs?).

My query:
Do I need/should I have a special type of wiring laid, in preparation for future LED lighting (either regular below-ceiling or LED down lights)?

Note: Due to the skillion-type roof, laying wiring in future will be a very expensive operation involving lifting the roof and cutting through the roofing blanket (horror) or cutting lots of wire-running holes in the soon-to-be installed new ceiling.

Posted Friday 26 Feb 2010 @ 12:08:51 am from IP #
LanceTurner
Key Master

Annette, no special wiring is needed. Most LED bulbs go straight into a batten fitting, either BC or ES base, the driver is built into the bulb. There are other dedicated fittings, also with the driver built in (or sometimes separate) but they will simply replace the batten holders when you get around to changing to LEDs.

Transformers are used to drop the 240 volt to 12 volt for the MR16 type halogen fittings, and the LED bulb equivalent. However, the LED bulbs still have an inbuilt driver, so in effect you are doing 2 levels of energy conversion, which is inefficient.

Many LED bulbs now run direct from mains power and have universal voltage input ranges (90 to 250 volts, for instance), so there's no need for anything else. Dedicated fittings usually have the LED driver built in or supplied as a separate power supply (which may be what you were seeing on the other website), but they still connect straight to mains power.

Posted Friday 26 Feb 2010 @ 1:29:34 am from IP #
Annette
Member

What a relief - thank you for that welcome info. Lance.

Posted Friday 26 Feb 2010 @ 5:13:47 am from IP #
ocular
Member

Googling got me here, did read the article on replacement lighting by LT and this has prompted me to get rid of the halogen downlights. Have a mixture of MR16 12V and GU10 240V downlights all 50 watts approx 30 in all. Installed about 10 yrs ago when all this was fashionable. All openings are 90mm and I am not motivated enough to cut all the openings as Lance did. In the past have tried CFL GU10 alternatives such as megaman 11w ($25-$30) but slow to turn on and wife was not happy where she had grown used to the great task ligting of halogens. The area is changing fast with the increasing design efficiency of LEDs, but I have to confess I am trialing spiral cfl 15W with E27 fittings (screw)in a 240 volt housing with a reflector that can fit straight into either a 70 mm or 90mm openings (larger is the standard halogen, gimbel fitting). can get the 90mm fitting with spiral CFL at my local lighting warehouse on special reduced from $21 to $19 ( Brand is Lummax Model LM90-FD and includes 15W CFL warm white). I believe has all the required Aust approvals. 3 of these lights are on trial and am impressed with the brightness at least in the living rooms/ bedrooms. At least as bright as the halogens but more diffuse but can't be dimmed. Not sure if I will get approval from SWMBO to replace the halogen task lighting. Have seen this combination (housing + CFL) as low as $11.95 + $2.95 plus pp
http://www.neco.com.au/cla-edison-screw-downlight-large (no picture - I think this is the 90mm cutout)

Here is the smaller one with picture (?70mm)

http://www.neco.com.au/cla-edison-screw-downlight-small

and CLA 15w spiral ww CFL for $2.95

http://www.neco.com.au/neco-15w-cfl-10000h-ww

These housings require a vertical depth of 16-18cm. It seems that the success of the "brightness" is from the reflector in the housing that enables one to use a standard CFL. I realise that this does promote CFL but it does seem a practical relatively cheap alternative to have more efficient lighting to fill in those 90mm holes while we are waiting for LEDs to become mainsteam.

In some locations it may be possible to down size to 11w if a suitable CFL can be found.

Posted Thursday 20 May 2010 @ 10:49:30 am from IP #
LanceTurner
Key Master

Ocular, you should definitely check out earthled.com again, they just released new versions of the Zetalux bulbs, cheaper and brighter (for the Zetalux Pro), the only drawback is the crap Aussie dollar at the moment. Sometimes it feels like we live in a developing country, the $ is so unstable...

Posted Friday 21 May 2010 @ 12:30:31 am from IP #
swanning_it
Member

Lance, Have you used these globes?

If so, how hot do they actually run? I noticed this warning on their site "*Precautions: Indoor Use Only. Do not install in enclosed fixture without proper ventilation. Do not install in wet location." and was wondering how they would go in an oyster style fitting? Certainly enclosed, but made for incandescent so I'm imagining the LEDs run cooler than incandescent?

Posted Friday 21 May 2010 @ 1:14:55 am from IP #
LanceTurner
Key Master

We used them on a retrofit of 8 downlights we wrote about in the last issue, they ran just mildly warm after hours of use, so they are fine, although those fittings are open at the back so there would be sme convective airflow. The whole bulb draws 6 watts, even though most still comes out as heat, it's not a lot to dissipate for a bulb that size, even in an enclosed fitting. They basically make those statements to cover their butts, no-one sensible would expose any electronic bulb directly to the weather and I can't think of many fittings that could overheat such a bulb.

The prob with oyster fittings is that the bulbs usually mount sideways, so this type of bulb is not the most suitable. I have been trialling some LED bulbs made from discrete LEDs from Deal Extreme, they are pretty simple units but so far, so good, they are worth a try, being dirt cheap. One of the units I'm trialling which has been great so far (getting 4-5 hours a night for the last couple of months) is http://www.dealextreme.com/details.dx/sku.26514

But for side moount bulbs, also have a look at http://www.dealextreme.com/details.dx/sku.35829 and even http://www.dealextreme.com/details.dx/sku.34391 and http://www.dealextreme.com/details.dx/sku.30211 although they are cool white units and quite large by the look of it.

Posted Friday 21 May 2010 @ 1:24:02 am from IP #

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