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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

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    • CommentAuthorGreenfish
    • CommentTimeJan 21st 2015 edited
    Where are we on the best (efficient, obtainable, affordable and reliable) replacement lamps for standard pendant bayonet light fittings? Went from incandescent bulb to CFL in old house hate the warm up times, electrician fitted "eco" (???) halogen 40W bulbs as a default in the new, but want to do better than that. Do I replace the bayonet holder with something else? Or will LED for such a fitting become universal? Would like to reuse my old lamp shades. Recommendations please.
    • CommentAuthorDarylP
    • CommentTimeJan 21st 2015
    ....your favourite forty thieves site lists lots of bayonet-fixing LEDs, take your pick!:bigsmile:
    • CommentAuthortony
    • CommentTimeJan 21st 2015
    • CommentTimeJan 21st 2015
    Have you tried the newer CFLs, MacSalvers have a few for a couple of quid.
    These LED filament bulbs are new to me. Certainly look the part in traditional fittings. Claim a long life (with warranty) and efficiency more than good enough (though overall output a bit low).

    • CommentAuthorrhamdu
    • CommentTimeJan 22nd 2015
    Posted By: Simon StillThese LED filament bulbs are new to me.

    Me too. Maybe wait until they bring out a version with a more 'traditional' colour temperature than 2700K?
    2700 is completely traditional - it's a tungsten style warm white.

    I bought a few - a couple to go in a pendant fitting that had previously had CFLs (2 of the 3 bulbs had gone). A bit pointless as it's behind frosted glass but the other options were too bright (!). The other is a golf ball bulb in a pendant where the bulb is visible from some angles. It's a little dimmer than the bulb it replaced (a 9 month old 'eco halogen' that was supplied with the fitting) but gives enough and definitely has a bit of the 'sparkle' that you normally lose with LED replacement bulbs.

    Will be interesting to see if the life is as good as claimed. They're certainly the first LED bulbs I'd be happy to have visible - they do a candle version that would look fine in a chandelier if that's your sort of thing.
    • CommentAuthorskyewright
    • CommentTimeJan 22nd 2015
    We recently got a couple of the 7W bayonet off this page at TLC. Very pleased so far.

    • CommentAuthorGotanewlife
    • CommentTimeJan 22nd 2015 edited
    skyeright - great link thanks. 7w and over 600 lm that's good. I also need some more powerful ones, has anyone seen a bayonet, pearl bulb with over 1000lm or even close? Simon I think that link is for trade only, is this it?


    Yes efficiency over 100lm/w but a lot dearer than the tlc site! Still no choices at over 700 lm. At least it seems normal to be able to find 100w/lm now.
    Has anyone found any LED pendant replacements that can be used on a dimmer switch?
    • CommentAuthorCWatters
    • CommentTimeJan 22nd 2015 edited
    I've recently purchased a few 9.5W 806 Lumen LED bayonet pendant bulbs from BnQ (Diall brand). Very impressed but non-dimmable.


    An earlier version (late 2013) was recommended by Which..


    Osram have a dimmable 10W 810 Lumen bulb but I've not tried it. One review suggests it might be sensitive to the type of dimmer.


    I've also recently tried some dimmable "filament" LEDs candle bulbs. One on it's own seems ok but five in one hanging lamp/chandelier flickered horribly and I've had to take them out. Might try another dimmer when I get chance.
    • CommentAuthorskyewright
    • CommentTimeJan 22nd 2015 edited
    Posted By: Gotanewlifeskyeright - great link thanks. 7w and over 600 lm that's good.

    That's what I thought too. We got a clear & an opal/pearl to test. Subjectively both are brighter than the "60W equivalent" CFLs they have replaced.

    has anyone seen a bayonet, pearl bulb with over 1000lm or even close?

    Not pearl, but we also got one of these (just over 900lm):


    SWMBO has a "cool white" one of those in a studio & is very pleased with the light quality.
    The first unit failed earlier this week (so after about 2 months), but we are assured that's highly unusual and a replacement was shipped out very quickly, & a pre-paid return label provided to allow the original to be sent back.
    • CommentAuthortorrent99
    • CommentTimeJan 22nd 2015 edited
    It's not really (easily) possible to make dimmable LEDs that use the old external dimmer switches.

    The dimmer switches work by "chopping" out parts of the mains sine wave (so you get less energy delivered).
    However, LED lamps (and CFLs) have their own power supplies that convert mains to a regulated low voltage (for LEDS). They REALLY don't like the chopped up mains signal that a conventional dimmer produces.

    To dim LEDs the bulb (well the power supply/driver circuitry in the bulb) needs to do it itself. That's why you get these bulbs that will do a few specific levels (Bright, not so bright, dim, off) in response to switching the light switch on an off in different patterns. The bulb circuitry recognizes the clicking pattern, and then drives the LEDs according to the "program".

    What's needed is a standard for a "dimmer switch" that sends a standard set of patterns to a bulb circuitry that then recognizes them and drives the LEDs (or other exotic lights!) accordingly. I suspect it'll come one day and it'll be A LOT more powerful than that, with each bulb being individually accessible over the internet! (via IPv6)

    EDIT: Just worked out how it could be done with existing dimmers and wiring, but you'd need a new type of bulb (& fitting) with 3 contacts instead of 2! (quick must patent that ;-) oh too late!))
    • CommentAuthorsnyggapa
    • CommentTimeJan 22nd 2015
    I am sure that you can get dimmable LEDs designed for mains dimmers, I imagine that they work by looking at the incoming waveform, seeing how "chopped" it is, then replicating using by electronics the approximate light level as instructed by the chopped waveform.

    I can't see why this wouldn't work , as long as the LED electronics were stable enough with the choppy mains signal.
    • CommentAuthorGotanewlife
    • CommentTimeJan 22nd 2015 edited
    Not sure what you mean by mains dimmer...This one works well:


    Dimming LEDs is a bit of a complicated area and all dimmers state a minimum wattage no lower than 9 or 10w BUT this is just the guaranteed minimum. I have this precise dimmer working well with 2 x 2w G4s through one on their own (YT35L) transformers for example, at the extreme low limit they do flicker but this dimmer allows you to set a min (and max) to avoid problems

    I hope this isn't too obvious: Non-dimmable LEDs cannot be dimmed, dimmable LEDs can be dimmed but only by dimmers designed for LEDs.
    • CommentAuthortorrent99
    • CommentTimeJan 22nd 2015
    I stand corrected! Didn't know they'd produced actual "dimmable" leds.

    From further reading however I can see they only work with what I'd call "special" dimmers. I.e. ones with trailing edge dimming. What I'd call an ordinary "mains" dimmer (working with SCR or triac, i.e. MOST dimmers in use in the UK at the moment), are leading edge and from what I'm reading are not compatible with LEDs whether dimmable or not.
    So if you want to use dimmable LEDs you'll usually need to change your dimmer.

    So I was sort of right! ;-)
    <blockquote><cite>Posted By: torrent99</cite>
    What's needed is a standard for a "dimmer switch" that sends a standard set of patterns to a bulb circuitry that then recognizes them and drives the LEDs (or other exotic lights!) accordingly. I suspect it'll come one day and it'll be A LOT more powerful than that, with each bulb being individually accessible over the internet! (via IPv6)

    There are a few already aren't there? 1-10v analogue, DMX, DALI. I think the problem is bulb replacements with built in driver where there's no 'data' connection. Different manufacturers are kludging dimming in non standard ways
    • CommentAuthorGotanewlife
    • CommentTimeJan 22nd 2015 edited
    Some LEDs work well with leading edge others, most, prefer trailing edge but I think all require a dimmer rated for LEDs as you say rendering all old or ordinary dimmers incompatible.

    Oh boy!!!! Things have really moved on since last I looked. Here is a 10w 1200lm bulb, 50.000hr, warm white, 270 deg beam angle, bayonet at only £15. 120w/lm:tongue::tongue:

    • CommentAuthorGreenfish
    • CommentTimeJan 23rd 2015
    LED filaments, I wonder how they make those? It also looks like the B2 bayonet fitting will be with us for a while yet, it is a question what fittings will remain once the market finally stablises.

    My issue is brightness as well as look. While 400lm is OK for a desk lamp, and there are lots of LED B22 offerings that size, I like to be able to turn on a main light and really see what is happening. A dimmer switch is great too, brightness only when needed. I'm looking for 1600lm (old 100W incandescent output) in a single bulb preferably dimmable, and they don't seem that plentiful (Gotanewlife's link noted). Maybe I am just old fashioned, perhaps I should have installed lots of small lights rather than central single pendant ones? Got caught out in the bathroom over this, although solved that by replacing the CFL bulkhead with 2 LED panels delivering a lovely 5600lm. Is the future going to be lumin limited for single bulbs? Rather than struggle for a single bright bulb (and a bank loan to buy it) should I look to replace my pendants with multi-bulb fittings?
    • CommentAuthortorrent99
    • CommentTimeJan 23rd 2015
    > Is the future going to be lumin limited for single bulbs? Rather than struggle for a single bright bulb (and a bank loan to buy it) should I look to replace my pendants with multi-bulb fittings?

    I have thought of doing that! Replacing 1 pendant bayonet fitting with 3 or 4 off the same ceiling rose. Not too clever, safe or pretty, but solves the lack of super bright single bulbs! ;-)
    Yes I got caught out too in bathroom, chandelier with CFL 1200 lm, 9w narrow beam LED luminaire directed into shower, very sexy, mirror with heat pad, no-touch operation and 20 plus leds around circumference: useless, wife can't do makeup in mirror with all lights on. Might have to have a look at aliexpress again.
    • CommentAuthorXT600
    • CommentTimeJan 25th 2015
    Being an electrician I've tried and tested many different LEDS in recent years. I learnt to my cost that many Ebay sellers were/are selling LEDS claiming long life, when in fact they give up after a couple of months or even weeks. They guy I purchased 100 GU10's from simply disappeared when I tried to contact him regarding the gradual failure of all these lamps, and I had to replace them all for my customers obviously. However, I can recommend this outfit, whose products are guaranteed for 5 years and the lamps I've purchased from them thus far have all been very good. They also sell trailing edge dimmers to suit their LED's.
    • CommentAuthorCWatters
    • CommentTimeJan 25th 2015
    Posted By: GreenfishLED filaments, I wonder how they make those?

    No idea. The ones I got are also E14 base - not much space for any electronics.
    • CommentAuthorrhamdu
    • CommentTimeJan 29th 2015
    Posted By: Simon Still2700 is completely traditional - it's a tungsten style warm white.
    Yes if you are talking about a standard GLS bulb. Perhaps I am wrong, but I assumed these LED 'filament' bulbs are trying to imitate those fashionable, dim, victorian-looking bulbs that run at a lower temperature. I believe they are meant to look like carbon-filament bulbs, and I would have thought something around 2400K would replicate the look better.
    Ok - I'd just assumed these were for anywhere you might see the bulb and wanted something a bit more traditional.

    In the light we're using it in it definitely adds a bit of 'sparkle' but the light level is a bit low.
    • CommentAuthorCWatters
    • CommentTimeJan 29th 2015
    Posted By: Simon StillI wondered the same thing

    http://electronics.stackexchange.com/questions/106815/how-do-filament-led-bulbs-work-looking-very-similar-to-incandescent-bulbs" rel="nofollow" >http://electronics.stackexchange.com/questions/106815/how-do-filament-led-bulbs-work-looking-very-similar-to-incandescent-bulbs

    Thanks for that. Will have to get out my magnifying glass.
    • CommentAuthorSteveZ
    • CommentTimeFeb 15th 2015 edited
    Re E14 base and components, my trial lamp went 'pop' the other day and I took it apart to see what was going on. The component count is small! The failure seems to be overheating on some of the surface mount LEDs. It failed with a series of flashes over ten minutes or so. If the photos are attached, the circuit board appears to contain some of the components and the LEDs are mounted back to back. I have another similar lamp on trial which is still ok, but has the LEDs mounted on a central pillar, so I assume there is a little more airspace around the hot parts. They both are cheap and the light output is a good colour and bright enough for a 5W rating
    Posted By: GotanewlifeI also need some more powerful ones, has anyone seen a bayonet, pearl bulb with over 1000lm or even close?

    I doubt it helps you, but I recently got a couple of Verbatim (! Verbatim = 8" floppy disks to me!) 12W 1100lm that I'm happy with: E22 or BC for £14.99 from Maplins (they're nearly twice that on-line).
    • CommentAuthorSprocket
    • CommentTimeAug 12th 2016
    Looking of a place to post this and I saw LED filament lamps mentioned above so thought this would do.

    Thanks to Elektor magazine that arrived today I saw this link to an old(ish. February 2015) but interesting and informative page about these LED filament lamps, including some comparative efficiency data:-

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