Screw-thread on downlight - what is it for?

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PhantomNVD

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#1047660 18-May-2014 22:47

Niel:
steve98: They box said equivalent to 40W but I would say they look more like a 60W.

That's because it is compared to total light output. Incandescent radiates in all directions, so when used in a down light or reflector fitting a large percentage is wasted into the ceiling/back while an LED bulb is directional so all the light is radiated forward. In the right fitting, an LED bulb is even more efficient than just the power saving.

so the fittings need to be changed also?

mattwnz

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#1047669 18-May-2014 23:52

FineWine: Consumer NZ has just tested LED's this month - they recommend Panasonic LDAHV8L27H2 though they are not cheap at $24 but you can buy them from Countdown

You can read all about their tests here http://www.consumer.org.nz/reports/led-bulbs

Cheers

You can get them cheaper at Briscoes when they have a sale. I got 30 % off. I have tested the panasonic ones, and the philips 8W and 13 W ones. The panasonic has a very good colour of light to it, where as the philips 8W one has a green tinge to it. The 13 W philips is possibily the best coloured light, but it is also the most powerful, and more expensive.

Fred99

13684 posts

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#1047845 19-May-2014 09:53

mattwnz: The 13 W philips is possibily the best coloured light, but it is also the most powerful, and more expensive.

These were on sale at New World supermarkets last week, about $22 each I think

. Not sure if they're still available at that price. I bought a couple of them, they seem okay. They are a larger physical size than the 8-10w LEDs - about the size of a typical 100W incandescent.

The Consumer article on LEDs was a bit scathing on spot/downlight performance.
"The spotlights were different – only two of the 12-volt LED bulbs had a higher light output than their equivalent halogen spots. The rest of the LED bulbs, both 230 and 12 volt, were disappointing. The lighting industry has more work to do to make these LEDs a true drop-in replacement for halogen spots."

richms

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#1047850 19-May-2014 09:59

I've found almost every 5w one to light the room better than what it replaced. Most halogen and gu10 downlights come with a very directional lamp which is hopeless for lighting a room.

Richard rich.ms

richrdh18

210 posts

Master Geek

#1047944 19-May-2014 12:22

I've replace all my R80 downlights with the Phillips 10W Led bulbs from Bunnings. Look a little bulbish in the light fitting, but you get over that. I replaced all other bulbs throughout the home with the same.
Used the 13W for bedrooms that had a single outlet. 5W x 3 for the hall way. Also used Verbatim (from Dove) for the Dim-able outlets.
Use to purchase a couple of bulbs a week so it wasn't too much of a direct hit in the pocket.
Found the Philips to put out good consistent light. So much so, that my wife never noticed the change.

Niel

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#1048271 19-May-2014 17:53

PhantomNVD:
Niel:
steve98: They box said equivalent to 40W but I would say they look more like a 60W.

That's because it is compared to total light output. Incandescent radiates in all directions, so when used in a down light or reflector fitting a large percentage is wasted into the ceiling/back while an LED bulb is directional so all the light is radiated forward. In the right fitting, an LED bulb is even more efficient than just the power saving.

so the fittings need to be changed also?

No, what I mean is LED bulbs are ideal for down light fittings as you do not have to rely on the (remarkably inefficient) reflector getting the light out. In a batten fitting (or pendant, or "wall washer") however they are not good, because no light spills onto the ceiling to scatter through the room.

You can never have enough Volvos!

Niel

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#1048278 19-May-2014 17:56

richrdh18: Found the Philips to put out good consistent light. So much so, that my wife never noticed the change.

I like them too, but they are just too fat for the fittings I had so used Viribright until I've found dedicated LED fittings that look good and work well, and fit the 35 holes in my house without having to cut it larger.
http://www.qualityledlighting.co.nz/

You can never have enough Volvos!

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MikeAqua

7773 posts

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#1054275 27-May-2014 12:49

andrewNZ: FWIW some old downlights do have a thread there. You install the frame, then screw in the reflector/trim.

If I was boss of the world, downlights would be banned (with the exception of a handful of cases).

And if you were boss of the world I would stage a coup

.

I'm with you on the old inefficient chimney style down lights, modern downlights are effective and efficient. We installed some 'dimmable' LED down lights in our kitchen. They are fully enclosed, can be insulated over top of, use very little electricity (the sparky measured it out of curiosity) and will last for tens of thousands of hours of use time. They provide fantastic illumination. We went for a colder colour in the kitchen but you could get warm white as well.

Mike

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