LED 2 Cell PR Drop Ins under $10, WPR3 vrs SMJLED2

I have numerous 2-cell flashlights I have collected over the years. I am upgrading the better ones to LED.

I know of only two types of 2 cell PR LED Drop in available for less than $10 dollars including shipping costs that have any kind of reasonable output. Any more than $10 and I should just buy new flashlights.

The SMJLED2 PR 2 (available from Sandwich Shop http://theledguy.chainreactionweb.com/product_info.php?products_id=924 ) and the WPR3 available on E-Bay from roostrfsh current item number 230080822089. Both of these I believe are single die as I see only two wires. This means they will go to just about zero light output in 50 hrs (see end). I know of no source for 4 die. The SMJLED PR 2 are $2 - $3 dollars cheaper than the WPR3 depending on quantity.


Anyone know of any other 2 cell PR LED drop in for under $10 with reasonable light output?

For what it is worth, here are some measurements I have taken on these using a Mag 2D with a cheap Lux meter.
All measurements taken at center of beam – 1 meter. Use measurements for comparison only. I have only a sample of two each, both samples yielded about the same results. A different order of bulbs might yield different results. This is just a snapshot of one purchase.

SMJLED2 PR 2 – 1600 Lux
WPR3 1900 Lux About 19% brighter than SMJLED2

For Comparison
Krypton .7 amp 2300 Lux About 44% brighter than SMJLED2, about 21% brighter than WPR3.

Meg LED Drop in 3500 Lux About 119% brighter than SMJLED2, 84% brighter than WPR3

Using an external power supply, obviously some voltage loss in setup.
SMJLED2 PR 2 WPR3
3.0 V 1480 100ma 1750 120ma
2.5 V 1000 70ma 1100 75ma
2.0 V 590 45ma 630 50ma

I read the CPF thread that showed the SMJLED2 going to almost zero output with fixed 3 Volts in 50 hrs. Others have not duplicated this (http://customlightfactory.com/phpBB2/viewtopic.php?t=69). I would like to try this myself if I build up a good supply.

Well, I for one would like to see further testing done to confirm or refute the only one extensive review that I was able to find on this site. I really like my SMJLED PR2 that I bought from Lighthound, but I am concerned about the 50 hour life of the LED. It also makes me wonder if other LEDs have the same problem that are also advertised having super long LED lives.

Being a novice with no equipment, the only test that I was able to do was a run-time test using my eyeballs and a clock. I put my SMJLED PR2 in a 2-AA Dorcy Gel Cell host with my new Rayovac Hybrid batteries. After running the light for 5 hours there appeared to be no lose of brightness according to my eyes.

I started the test too light at night and went to bed after only watching it for 5 hours. The next morning after running the light all night, I check it again at 13 hours and the light was about 75% as bright as my new Safe-Light was on its highest setting.

I read all these reviews about long run-times, but it really does not sink-in until you do one yourself. Man, that is a lot light for just 2-AA batteries!!

FlashlightReviews.com got 40 hours to 50% on the original SMJLED PR2. The test was terminated at 60 hours with no problems noted and output was just a little below 50%. This was on 2 D cells.

PR2-W1-WVR LED FlashLight bulb $4.95 + shipping.
http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=LIGHTS
The other bulbs on that page are either too dim and/or have terrible beam patterns.

They work reasonably well in 2AA lights with small reflectors. On larger reflectors they tend to produce a donut hole effect. By frosting the sides of the LED, BUT NOT THE TOP, with some sandpaper I was able to blur the ring created by the reflector into the spot from the front of the LED to get a reasonable beam pattern.

Note the bulb is 1-5V. I have run 1 of the bulbs on 4NiMH for close to 100 hours. So they are quite reliable. About 1/2 hour/day every other week for a year now. I was alternating flashlights.

I have relpaced the bulbs in my 2AA lights with the SMJLED PR2 (the good 4 die ones) so do not have reliability of the superbrightleds' bulb on 2AA. I do not expect them to be worse than on 4AA though.

DonShock said:

FlashlightReviews.com got 40 hours to 50% on the original SMJLED PR2. The test was terminated at 60 hours with no problems noted and output was just a little below 50%. This was on 2 D cells.

Click to expand...

I am new to all this LED technology, so bare with me. The only LED life comprehensive test that I read about was on the new single die that was driven at a constant 3 volts. A fresh pair of my new Rayovac Hybrids cells would only be around 2.4 volts (I guess) and dropping during normal use. Logic tells me that the expected LED life should be much greater using the Hybrids under normal use than being run at constant 3 volts.

All kinds of questions come to mind, since I am so new to all this and a lot of what I read is beyond my comprehension. If the original PR2 SMJLEDs were better, why not bring those back and drop the newer version? I wonder if the WPR3 is better or worse than the new PR based SMJLED? Who makes the PR based LED in my little yellow stubby Dorcy 4-AA? Does it run of off 3 volts or 6 volts? When, if, or can a XR-E LED be made to fit a PR base?

I have SMJLED PR2 original,

http://home.mchsi.com/~lambda_lights/pr2bulb.htm

and PR2-W1-WVR LED FlashLight bulb

http://www.superbrightleds.com/cgi-...?product=LIGHTS


SMJLED is brighter, and gives better spot.

PR2-W1-WVR is dimmer, and gives more flood.

At least in my 2AA torches, using nimh or alkaline.

PR2-W1-WVR draws much more current at 3v.

But it does fine in my 6v, working @ 4.8v PIR lights.

See also direct comparison...

https://www.candlepowerforums.com/threads/114655

less so...

https://www.candlepowerforums.com/threads/109867&highlight=smjled+abvidleduk

Bearcat said:

If the original PR2 SMJLEDs were better, why not bring those back and drop the newer version?

Click to expand...

There is a 30% price difference. Online stores tend to compete on price.
The cheapie bulbs cost $8 each. The SMJLED LED alone is $5.25 at the Shoppe.
The problem is not knowing what you will get. One CPF member ordered 2 bulbs and reported he got 1x4 die and 1x1 die.

Bearcat said:

Who makes the PR based LED in my little yellow stubby Dorcy 4-AA?

Click to expand...

LEDcorp. Note the LEDcorp bulb is frosted on the top and the MJLED/SMJLED are smooth. The LEDcorp bulb will not work on 2AA lights.

Bearcat said:

IWhen, if, or can a XR-E LED be made to fit a PR base?

Click to expand...

A PR2 base is 9mm diameter. The XRE is 6x9mm rectangle 11mm diagonal. 11mm into 9mm no fit.
I seen modders do wonders clipping off the corners of the XRE.
Soeul and Edison are putting the XRE die into round luxeon style cases. they will fit. But you are adding $8 cost ($24 retail) to an $8 bulb. Remember to most people A FLASHLIGHT IS A $5 THING.

I for one feel that PR drop ins have a severe limitations, because you're limited to the thermal mass of the drop in for the most part as the body doesn't conduct heat too well in a normal PR socket.

Thanks everyone for all your help.

In all the hodgepodge of in-depth over my head information, some how I was led to believe or misunderstood that all of the 4-die versions have been replaced with the newer single die versions and no more 4-dies versions could be purchased.

Well, I E-Mailed Lighthound and they say that they have only sold and still sale the 4-die version. That is really good news if anyone is interested, since it is my understanding from reading some of the posts that the run-times and bulb life is longer with the 4-die version. Someone correct me if I have misunderstood this information too.

Is this SMJLED PR drop-in significantly brighter than the Nite-Ize?

How's the color?

Hellbore said:

Is this SMJLED PR drop-in significantly brighter than the Nite-Ize?

How's the color?

Click to expand...

I read that they are good bit brighter than the Nit-Ize and the SMJLED PR that I have in my Dorcy Gel Bright has a good white color and plenty of thow.

Hellbore said:

Is this SMJLED PR drop-in significantly brighter than the Nite-Ize?

How's the color?

Click to expand...

This SMJLED PR drop-in FOCUS BETTER than the Nite-Ize in fixed focus reflectors.

The 4 die SMJLED PR is a cool white. (Lighthound)
The SS PR is a warm white. (Sandwich Shoppe)

So now it looks like we might actually be able to get the 4 die from lighthound. Interesting. Do we know for certain that two wires means 1 die and three wires means 4 die? And does 4 die mean 4 chips and less drive to each chip and therefore longer life? Not sure I understand this die thing.

I guess we may have to expand to WPR3 vrs SMJLED2 vrs SMJLED. I read some reports that the 4 die was definitely brighter and others that it was not. The SMJLED2 is still the cheapest at 5 for $27. One could spend a lot of money just doing comparisons and life tests on each of these.

sguyer said:

...
Using an external power supply, obviously some voltage loss in setup.

SMJLED2 PR 2 WPR3

3.0 V 1480 100ma 1750 120ma
2.5 V 1000 70ma 1100 75ma
2.0 V 590 45ma 630 50ma
...

Click to expand...

Woah woah WOAH!

There is a serious discrepancy here.

I have an SMJLED PR2. It's from the Sandwich Shoppe, and it's stamped "S.S.2 cell". It's almost virgin - it probably has only 15 minutes of runtime on it. The current readings you posted are nowhere near what I measure on mine.

Here's what I see:

3.0v 184 ma
2.5v 125 ma
2.0v 92 ma

I'm pretty sure these numbers are correct because they've been measured on both the analog meter of my bench power supply and a Fluke 8050A DMM in series with the LED.

These numbers don't tell the whole story, however.

The weird effect I've noticed is that the current keeps going up as the LED warms up. Here's a quick table of current at 3 volts, as the LED warms up:

0:00 184 ma
0:52 200 ma
1:31 205 ma
4:12 210 ma
...


To me, it looks like my SMJLED PR2 goes into thermal runaway very rapidly at 3 volts, so I'm not surprised at all the Newbie's SS SMJLED PR2 died at 50 hours. Actually, I'm surprised it lasted that long.

Assuming the converter is 75% efficient, at 3 volts the LED is being driven at 138 ma. Other 5mm 4-die LEDs I've seen are rated at 80 ma continuous forward current and 100 ma peak current for 0.1msec, so 135 ma continous is wayyy too much.

Anyway, it appears my SMJLED PR2 and yours exhibit totally different behavior, so I suspect the SMJLED PR2 was silently redesigned without telling anyone. Since yours only draws about 54% of the current of the SS SMJLED PR2, it's likely to last much longer than 50 hours.

Toshi

This is what I got for the PR2-W1-WVR LED FlashLight bulb

http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=LIGHTS





My original Lambda SMJLED PR2's draw 85ma @ 2.4v

http://home.mchsi.com/~lambda_lights/pr2bulb.htm


My Tektite PR2 draws 240ma @ 2.4v

abvidledUK said:

This is what I got for Superbright WPR3 last year.



My original Lambda SMJLED PR2's draw 85ma @ 2.4v

My Tektite PR2 draws 240ma @ 2.4v

Click to expand...

Here's what I get for my SS SMJLED PR2:

1.2v 63ma
1.5v 70ma
2.4v 113ma
3.0v 183ma

I don't understand why you're referring to it as the "Superbrightleds WPR3". As far as I know, SBL doesn't sell the WPR3?

Toshi

TMorita said:

I don't understand why you're referring to it as the "Superbrightleds WPR3". As far as I know, SBL doesn't sell the WPR3?

Toshi

Click to expand...

You're quite right.

I meant the PR2-W1-WVR LED FlashLight bulb

http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=LIGHTS

Errors corrected

(Damn that cut & paste !!)

This sure is interesting stuff.

I need help in choosing which one of the drop-in PR2 LEDs is the best, because I need around 6 of them for my old 2 cell flashlights. I just know that there is a flashlight Guru on the site that knows the answer.

I have to admit to a gross error. I guess I was more concerned with brightness than getting accurate current readings. I was using an old Weston analog current meter and I was reading the wrong scale. Try taking my current reading and double. And since they change with time, just through my readings out and use the other readings in this thread. I went back and used two digital meters to verify that the analog meter readings double were in the ballpark.



The important thing here is that the SMJLED2 has not been fixed. I measured the same increasing current. As for the WPR3, add an additional 30 to 40ma to the SMJLED2 readings and you are there. And the current to the WPR3 also increased, toping out +30ma higher.

Which to buy is a really a good question. I also leave that to others.

PR2-W1-WVR LED flashlight bulb
The 4 die SMJLED PR is a cool white. (Lighthound)
The SS PR is a warm white. (Sandwich Shoppe)
WPR3 - May be the brightest

If the Lighthound version really is 4 die, maybe that is the way to go, but you may be sacrificing brightness for long life of the LED. If you want cheap, than sandwich shop.
Would be nice to see a new life test on all of these.