Source for MR16 LED

[spartan]

I'm looking at replacing my 12 volt halogen globes with LED (36 LED) anyone got a good source and price for the globes?

[doug1]

Have a look at the Jaycar site I believe they have various mr16 lamps including LED

Doug

[duckman]

Jaycar
http://www.jaycar.com.au/productView...Max=&SUBCATID=

or Altronics
http://www.jaycar.com.au/productView...Max=&SUBCATID=

Cutter electronics

http://www.cutter.com.au/search.php

to name just three.

[spartan]

Thanks....had a look at those sites....Its a bit disappointing that the technology doesn't seem to be there yet to replace the 50W 12V halogens with an equivalent LED.

The price is pretty steep too, but I'd probably pay that if I could get one that was the equivalent of 50W Halogen but only consumed 3W....

[duckman]

Thanks....had a look at those sites....Its a bit disappointing that the technology doesn't seem to be there yet to replace the 50W 12V halogens with an equivalent LED.

The price is pretty steep too, but I'd probably pay that if I could get one that was the equivalent of 50W Halogen but only consumed 3W....

I've been researching this subject over several weeks for 'Homebrew" headlight(s) for my mountain bike and have learnt that Luxeon Stars produce the most light for the least amount of power but what you're after isn't going to be available for some time to come.

http://www.lumileds.com/

If you're thinking that you'll save electricity and therefore money by running LED's you might have to rethink your idea. As I understand it, dropping the 240v mains supply to 12v to power 'low voltage' lights consumes just as much electricty as running 204v lights. There is a thread around here somewhere in which people who are much more knowledgable on this subject than me made statements to that effect, IIRC.

BTW, wattage is a unit of power and doesn't give a measure of the amount of light produced. Its especially important to get as accurate a measure as possible when comparing two very different types of light sources.

[bresmith]

Have you had a look on EBAY.
http://cgi.ebay.com.au/2-x-30-LEDs-M...QQcmdZViewItem

Still fairly expensive but l guess you save in the long run.
Do you know what the light out of these things is like. I would consider replacing my downlights if it was similar.

Brent

[spartan]

I believe the best of the LED produce about 50 lumen...I'm trying to find out what standard 50W Halogen puts in terms of lumen to get an apple for apple comparison.

[duckman]

I believe the best of the LED produce about 50 lumen...I'm trying to find out what standard 50W Halogen puts in terms of lumen to get an apple for apple comparison.

It depends on the colour and the 'binning' of the LED. Assuming you want white light then as a general rule

Luxeon III, 3w Luxeon stars put out 80 lumen when driven at 1000 mA but only 65 lumen @ 700 mA

Luxeon V, 5w, 120 Lumens @ 700 mA.

Currently, Cree brand Luxeon Stars put out the most light for the least current.

Website: http://www.cree.com/products/xlamp.asp

BTW, LED 'globes' are on special at Altronics.
http://www.altronics.com.au/index.as...=item&id=X2150

HTH,

Mark.

[GraemeCook]

Spartan

Have you tried any yacht chandleries? - yachties are very careful on power consumption and minimising battery weight.

You might look at Whitworths in Australia or West Marine in USA.

Cheers

Graeme

[Master Splinter]

Have a look at www.neco.com.au

They do a few types of replacement bulbs for halogen fittings, except their bulbs are flourescent - so an 11 watt bulb gives you 50 watts worth of output. The beasties are supposed to last for 15,000 hours, too.

They do list a LED fitting, but at over $100, you'd want a pretty good reason to use one. As I recall, LED lights are not much more efficient than regular incandescent light fittings.

[bresmith]

As I recall, LED lights are not much more efficient than regular incandescent light fittings.

I thought LED's were many times more efficient as they virtually don't produce any heat which is where most of your energy is used. The one's l have seen are only about 1.7Watts which is 30+ times more efficient than a 60 Watt incandescent. Whether they produce as much light is another question. The one on EBAY claims to produce 45,000 mcd of warm white light. How does this compare to a standard halogen?

[duckman]

I thought LED's were many times more efficient as they virtually don't produce any heat which is where most of your energy is used. The one's l have seen are only about 1.7Watts which is 30+ times more efficient than a 60 Watt incandescent. Whether they produce as much light is another question. The one on EBAY claims to produce 45,000 mcd of warm white light. How does this compare to a standard halogen?

LED's are more efficient but they most certainly produce heat. The Luxeons to which I referred in my post, once they reach 3w, require heat sinks otherwise they'll disappear in a puff of magic smoke. :eek:

The point that still seems to be being lost in recent posts is that when running low voltage lights off mains (240v) power, the full voltage passes through your meter and so you pay for it, before it reaches the transformer or other circuit that 'knocks it down' to a level that can be used by the light.

I don't think that there is no benefit to either the hip pocket of the environment because the same amount of electricity is being generated and used.

[bresmith]

I realise that by using a 12v transformer to reduce your voltage from 240v that you are not going to reduce the amount of electricity you are going to use. Otherwise we would have 110v like the US as a standard. If however the appliance that it is attached to this voltage uses 1.7watts (LED) as opposed to a 50watt halogen, then you are going to use 30 times less electicity to light the LED. Hence benefit to hip pocket and environment. Are my thought processes right about this or have l gone completely mad.

[duckman]

I realise that by using a 12v transformer to reduce your voltage from 240v that you are not going to reduce the amount of electricity you are going to use. Otherwise we would have 110v like the US as a standard. If however the appliance that it is attached to this voltage uses 1.7watts (LED) as opposed to a 50watt halogen, then you are going to use 30 times less electicity to light the LED. Hence benefit to hip pocket and environment. Are my thought processes right about this or have l gone completely mad.

My knowledge on this topic is exhausted. As I said to the OP in my first reply, there are others around here who are far more knowledgeable than me on this topic. I'm surprised that at least one of them hasn't jumped in before now.

As far as the power consumption of a 1.7w LED versus a 50w halogen we would have to know how much power is lost in the tranformer or whatever circuitry is used before each light and then add that to the amount of power used by each light respectively.

Whilst I realise that you may be just using the figures of 1.7w LED and 50w halogen to illustrate a point, its a given that the LED won't be producing as much light as the halogen so perhaps comparing their respective power consumptions isn't relevant in terms of which is better for lighting a room if the LED just isn't up to the job. In terms of overall efficiency then I think the comparison would be valid.

[Master Splinter]

First off - for comparing basic efficiency, have a look at the wattage.

Two 12 volt, 50 watt halogens consume as much energy as a single 240 volt, 100 watt bulb - in fact they will consume a little bit more due to transformer losses. You typically have to replace one standard bulb with two halogens, so the halogens will cost a bit more to run unless you want to put up with significantly less light.

(Don't even think of the cost of replacing transformers that stop working for no apparent reason.)

Dimming (halogens or incandescents) doesn't really save money; the efficiency of the bulb goes down so you are getting less light for your lighting dollar. It's always better to have fewer, but higher wattage bulbs than lots of low wattage bulbs, as the higher wattage bulbs are operating more efficiently.

Then - compare the light output of the bulbs.

Usually this is in lumens per watt (how much light you get out for the amount of electricity you put in). Sometimes this is printed on the packaging.

Standard incandescent bulbs are about 7-24 lumens per watt
Halogens are about 12-36 lumens per watt
Standard fluourescent 30-100 lumens per watt
Compact fluourescent 44-80 lumens per watt
Really good (luxeon star) LEDs are about 30 lumens per watt