CREE MR16 LED's Lowdown

[yatzki]

Hi all,

I did lots of research here on CPF before posting but I still have a few questions.

Sorry for bothering guys with so many question right off the bat. It just doesn't seem to be addressed anywhere else and this seems like the right forum.

1. Its my (basic) understanding that CREE is the gold standard in LED manufacturing, so most of my research centered around this brand. Am I correct?
2. This is for my kitchen/dining/living rooms and I already used, at some point, 20W halogens and I'm fine with it. The 3 watt CREE's floating around the Internet seem more that fine.
3. Am I correct in assuming that "Warm Temperature" lighting is better for my application that "Bright White"? (The halogens do have a warmer feel.)
4. If I'm wrong for the above, which one do think is better for my application?
5. Many merchants offer either 1x3 watts or a single 3 watt bulb. Which one would be a better option?
6. My understanding is that CREE doesn't actually make the MR16. Others buy the chip and build it themselves. Correct? If so, is there a difference?

These LED seem to have made great advancements in the past few years so some older equations should no longer apply.

It also seems that some CREE's of the same wattage are older models.

Assuming that I was right with my assumptions, would the following a make a good purchase? (In my case.)

http://bit.ly/11YgeN
http://bit.ly/19IYDU

Again, sorry for jumping on you all like this.

Ben

 

[LEDninja]

Its my (basic) understanding that CREE is the gold standard in LED manufacturing, so most of my research centered around this brand. Am I correct?
Cree EZ1000 dies are used in the Cree XRE, XPE, MCE; SSC P4, P7 LEDs. Any of the 5 would work equally fine.

This is for my kitchen/dining/living rooms and I already used, at some point, 20W halogens and I'm fine with it. The 3 watt CREE's floating around the Internet seem more that fine.
What kind of fixture will the bulbs go into? LED bulbs need a lot of ventilation for cooling.

Am I correct in assuming that "Warm Temperature" lighting is better for my application that "Bright White"? (The halogens do have a warmer feel.)
If I'm wrong for the above, which one do think is better for my application?
This is more of a personal preference. Cree based bulbs usually do not have the blue/purple tint of the early 5mm LED ones.
EDIT
The cool white is brighter, the warm white is usually more pleasing to people used to candles, fireplaces and incandescent bulbs.
/EDIT

Many merchants offer either 1x3 watts or a single 3 watt bulb. Which one would be a better option?
A 1*3W bulb only give you 100 lumens.
A 3*1W bulb will give you 180-200 lumens but costs $15 more.
This is due to the LED being a lot less efficient when you drive them hard.
More important is the beam angle and shape. Some LED bulbs have a flashlight type beam - hotspot & spill (the 3*1W I linked to). Others have a big spot of light (the 1*3W). Both are narrower than a typical Halogen which is more of a flood

My understanding is that CREE doesn't actually make the MR16. Others buy the chip and build it themselves. Correct? If so, is there a difference?
BIG difference. I bought a 36 LED light bulb 2 years ago and it is still running. NOTE THE UL LISTING FOR THIS BULB. This board is filled with threads of multiple LED bulbs that die within a month. So a bulb from a reliable manufacturer is critical. At least a retailer that will check out the manufacturer, not just carry the cheapest junk available.
Phillips should be releasing their LED bulbs into the North American market in a couple of months (not Cree based LEDs). I think the quality assurance of the design and manufacture is better than the 'fly by night' approach of some Chinese companies.
And the Phillips bulb will have CSA APPROVAL or UL LISTING or ETL LISTING.
The CE sticker on the current crop of cheap LED bulbs are only good for 230 volt countries, not Canada nor the US where the voltage is 115V.
24V bulbs like the MR16 are worse as no approval is required so the cheap companies do not bother to test for safety,
EDIT
Notice from other threads GE actually have LED bulbs up to 7W at Walmart and Sams Club in the US.
/EDIT

EDIT2
I saw the Philips bulbs at Home Depot. UL listed. There are E26, GU10, MR16 bulbs.

 

[lightime]

Sorry to bring up a old thread but I had a question about the MR16 CREE LED lights. I am wondering what type of led driver they have inside? How efficient are the internal drivers of these?

The ones you posted (below) say power consumption is 3watt and 3.6watt respectively that means very high efficiency of the drivers no?

A 1*3W bulb only give you 100 lumens.
A 3*1W bulb will give you 180-200 lumens but costs $15 more.

Thanks!

Its my (basic) understanding that CREE is the
gold standard in LED manufacturing, so most of my research centered around this brand. Am I correct?
Cree EZ1000 dies are used in the Cree XRE, XPE, MCE; SSC P4, P7 LEDs. Any of the 5 would work equally fine.

This is for my kitchen/dining/living rooms and I already used, at some point, 20W halogens and I'm fine with it. The 3 watt CREE's floating around the Internet seem more that fine.
What kind of fixture will the bulbs go into? LED bulbs need a lot of ventilation for cooling.

Am I correct in assuming that "Warm Temperature" lighting is better for my application that "Bright White"? (The halogens do have a warmer feel.)
If I'm wrong for the above, which one do think is better for my application?
This is more of a personal preference. Cree based bulbs usually do not have the blue/purple tint of the early 5mm LED ones.
EDIT
The cool white is brighter, the warm white is usually more pleasing to people used to candles, fireplaces and incandescent bulbs.
/EDIT

Many merchants offer either 1x3 watts or a single 3 watt bulb. Which one would be a better option?
A 1*3W bulb only give you 100 lumens.
A 3*1W bulb will give you 180-200 lumens but costs $15 more.
This is due to the LED being a lot less efficient when you drive them hard.
More important is the beam angle and shape. Some LED bulbs have a flashlight type beam - hotspot & spill (the 3*1W I linked to). Others have a big spot of light (the 1*3W). Both are narrower than a typical Halogen which is more of a flood

My understanding is that CREE doesn't actually make the MR16. Others buy the chip and build it themselves. Correct? If so, is there a difference?
BIG difference. I bought a 36 LED light bulb 2 years ago and it is still running. NOTE THE UL LISTING FOR THIS BULB. This board is filled with threads of multiple LED bulbs that die within a month. So a bulb from a reliable manufacturer is critical. At least a retailer that will check out the manufacturer, not just carry the cheapest junk available.
Phillips should be releasing their LED bulbs into the North American market in a couple of months (not Cree based LEDs). I think the quality assurance of the design and manufacture is better than the 'fly by night' approach of some Chinese companies.
And the Phillips bulb will have CSA APPROVAL or UL LISTING or ETL LISTING.
The CE sticker on the current crop of cheap LED bulbs are only good for 230 volt countries, not Canada nor the US where the voltage is 115V.
24V bulbs like the MR16 are worse as no approval is required so the cheap companies do not bother to test for safety,
EDIT
Notice from other threads GE actually have LED bulbs up to 7W at Walmart and Sams Club in the US.
/EDIT

EDIT2
I saw the Philips bulbs at Home Depot. UL listed. There are E26, GU10, MR16 bulbs.

 

[blasterman]

Its my (basic) understanding that CREE is the gold standard in LED manufacturing, so most of my research centered around this brand. Am I correct?

A better explanation would be is that it's really hard to go wrong with Cree because they do a lot of things very well and are kind of an industry litmus. Obviously if you had a choice of bulbs running Lux IIIs -vs- Cree P4's the later would be the better choice. However, this is not a reason to discount K2's or Seouls because they have their niche and in some respects have advantages; K2's because of their robustness and Seouls for their uber_high CRI for instance.

Am I correct in assuming that "Warm Temperature" lighting is better for my application that "Bright White"? (The halogens do have a warmer feel.)

Entirely subjective and a personal choice. Personally I find neutral white emitters (around 4100k) too sterile for a living room in the evening, unless it's accent lighting. While warm-white Crees can't compete with a 50-watt halogen in terms of brightness (not even close) the LED lacks the annoying green/yellow of the halogen and just look 'pleasant' to my eyes.

My understanding is that CREE doesn't actually make the MR16. Others buy the chip and build it themselves. Correct? If so, is there a difference?

Cree makes many of their own fixtures as well, but I'm not sure about MR16. Cree's commercial fixtures though have a superb reputation. LED based MR-16s on the other hand have mixed reviews around here because the driver used has the biggest bearing on quality.

A line voltage MR16 has to convert mains voltage, which lets say for the U.S. is 120volts AC to low voltage / high current DC. This is just not something you do with a $1.00 chinese circuit, or do it reliably. So, when I see Cree based MR16's on a web-site for $17.99 I get a little skeptical.

I would try to stick to name brands as mentioned above. The Phillips has some good initial press, but it's lack of using Cree's shouldn't deter you. Obviously Phillips will want to use their of LEDs rather than buy them at OEM prices from the main competition

 

[LEDninja]

The 1*3W and 3*1W by Chinese manufacturers refer to LED power (ignoring the power used by the driver). So actual power at the bulb socket is higher.
'1W' usually means the LED is driven at 350mA. This is actually 1.2-1.25W.
'2W' usually means the LED is driven at 500mA.
'3W' usually means the LED is driven at 700mA.

Philips probably rates their bulbs at the socket. I cannot see into the frosted 7W bulb I bought but the 7W spot versions of the MasterLED have 4 Luxeons. 4*1.25W only add up to 5W so the driver is probably using up 2W to make up the 7W.
Note the bulb is rated 155 lumens.

Using the same ratio of LED to driver power the 3*1W bulb is probably using 3.6W LED + 1.5W driver or 5W+. (I almost burnt my fingers on the heatsink of mine. No problem holding on to 3*L0Dce strapped together so the bulb is definitely using up much more than 3W.)
Still 180 lumens for 5W is still better than 155 lumens for 7W.

3x1W Cree vs, 7W masterLED.
This is not a fair comparison as the 3x1W has focussing optics to produce a bright hotspot. BTW not shown clearly is the optics produce a hotspot/spill light identical to 3*L0Dce which is not that useful for most household tasks. I found the 1*3W more useful as it produce a much bigger hotspot with smoother falloff despite the lower lumens.

7W IKEA CFL vs, 7W masterLED.
Just remember 7W IKEA 2 for $10, 7W masterLED $29.95, 3*1W $35 (+shipping +customs brokerage).

 

[bhvm]

That crappy bulb above has an efficiency of ONLY 22 LM/w... but i am happy that Phillips have put up realistic ratings.

If thats all what LEDs can give.. we were better off with Incandescents.

 

[LEDninja]

The Philips bulb uses LUXEONS or LUXEON rebels (depending on the source). As Philips Lumileds has problems manufacturing rebel 80s & 100s in quantity I suspect rebel 60s.
The Cree based bulbs are roughly twice as efficient. The Zetalux 7 gives 350 lumens for the same 7 watts (more if you don't mind cool white).
So buyer beware. Unless the bulb uses Cree XR-E or XP-E LEDs, CFLs are more efficient.

One thing you have to keep in mind. Most LED bulbs shoot light forward. So the LUX NUMBERS are higher than the LUMEN numbers indicate. It is better to compare an LED bulb with a reflector incandescent instead of with a globe type incandescent.

I have found many applications where a 2W or 3W Cree is sufficient.
That works out to 7W to 10W incandescent. Try find a 7W incandescent. Unless you get candelabra socket lamps and use night light bulbs.
Again CFLs in the 2-3W range is hard to find.

For general lighting a Zetalux or Evolux (1000 lumens for 13W) makes more sense. Due to the high cost of LED bulbs, unless you run them at least 12 hours per day, it does not make economic sense.

 

[blasterman]

It is better to compare an LED bulb with a reflector incandescent instead of with a globe type incandescent.

That's a good point, and refreshes my bafflement at why the Zetalux and Evolux use those thick diffuser domes and take such a big efficiency hit. If you want directional light, then neither are a good choice because of their diffusion. But neither are a good choice if you want a true, wide angle light source either. They seem orientated towards the usual recessed lighting applications and look out-right dorky inside the sample table lamp used for comparison.

If you need a wide angle light that truly simulates a globe incan or spiral CFL then it would make more sense to mount 4 high power LEDs around a 1 inch copper/alu cylinder, and then use extensive radial fins above and below the LED ring for entirely passive cooling. Then, mount an external cylinder of faceted clear acrylic around the fins for diffusion. This will provide a 360 degree light source, and the acrylic diffuser will darn near provide double the light transmission over the Zetalux and Evolux plastic domes. Stuff the driver inside the middle cylinder.

Also some good points made about driver efficiency. Some of the micro Chinese drivers used in the cheaper, no brand bulbs are lucky to hit 50% efficiency.