$6.25 Elly 1 Watt has boost/regulated 2h 40m!

[vetkaw63]

What is the run time for the direct drive on high?
Thanks,
Mike

 

[joedm]

roughly speaking... around 60-90 mins before the output is low enough to tell that it actually is lower, probably around 50% of original output. but thats just a guess.

[edit] actually that was for the LOW mode... I haven't run it on HIGH for too long because it gets real warm...
I'd guess less than 30 mins if the leds doesn't cook... HIGH has the current at 1.3A measured from the tailcap.[/edit]

 

[Aepoc]

Here's some beamshots comparing a Cree and Seoul Elly with a Kroma and PD:

https://www.candlepowerforums.com/threads/158520

 

[johnny13oi]

My Elly draws about 600ma from the tailcap from a fresh NiMh battery. Is this normal compared to everyone elses drawing about 1A from the tailcap?

 

[ScottW]

I only have an n of two, but I just measured mine at 1.24 and 1.05 A at the tail with a fresh NiMH. They appear to have roughly equal brightness, although there's a minor difference in tint. But I'd say 600 mA sounds pretty low.

 

[protein_man]

I was unlucky, my elly was only drawed 600ma at the tailcap so I modified it to a direct drive off a 14500 and a cree.

 

[johnny13oi]

would the ones drawing over 1A at the tailcap be much brighter than what it is now? Because I am actually pretty happy with the performance of the Elly right now in the dark.

 

[Bertrik]

I found it depends on the kind of current meter too. My cheapo multimeter at home measured just 0.6A from the tailcap. A better one at work indicated 1.2A from the same battery. I can imagine that the cheaper multimeters are not very accurate at measuring high current and are dropping more voltage when put in series with the battery and the Elly circuit.

 

[vetkaw63]

I have read that it has something to do with the pulsing of the circuit. Cheaper meters don't read this as well.
I don't think it matters what it reads at the tail cap. Read at the emitter.
Mike

 

[Bertrik]

The current is read from the tailcap because it's easier to do than measuring it at the emitter. I added an input capacitor (100 uF) to my Cree Elly, so the pulsed nature of input current should be greatly reduced but I still see the same low reading on my home multimeter.

 

[2xTrinity]

Interesting. I've tested my Elly to be about 1.2A at the tailcap with a Premium alkaline, or NiMH cell, and more like 600mA at the LED. The current at the LED cannot possibly be accurate without violating conservation of energy (1.2A * 1.2V = 1.44W in, 600mA * 3.5V = 2.1W out) Based on the brightness I've been seeing, I suspect that the input is closer to reality, and the output current is pulsed, therefore erroneous.

 

[johnny13oi]

I have read that it has something to do with the pulsing of the circuit. Cheaper meters don't read this as well.
I don't think it matters what it reads at the tail cap. Read at the emitter.
Mike

This would explain my situation GREATLY. I just bought a cheapo $3 meter just for the purpose of finding out what voltage my batteries are.

 

[Curious_character]

Wow, that was the easiest mod I've ever done. I got three Ellys and some Cree and Seoul stars from DealExtreme. Put a Seoul into one Elly and a Cree into another. The total lumen output for both the Seoul and Cree lights is about 52, nearly three times the original. Lux at one meter is about 1600 for the Cree and 1300 for the Seoul. The Cree light makes a beautiful tight spot, and the Seoul is more floody.

Run time for the Cree modded light is a little over 1-1/2 hours on a 2 Ah Eneloop NiMH, with the light at 66% of the initial value at 1-1/2 hours. (It dropped 11% in the first minute, which isn't unusual.) It was still going after that, but the light level was about 25% of the initial level.

I dealt with the loose head problem by wrapping a single turn of ordinary black vinyl electrical tape around the threads. It makes the head nice and snug. This probably isn't a terribly durable solution, but then they're not particularly durable lights, either.

It looks like the vendor discovered how easy the Cree mod is, too -- about three days after I ordered the Ellys, what shows up but the Cree look-alike for about ten bucks. I have two of those on the way.

These are a lot of fun for a few bucks, and a great platform for experiments. Thanks, DealExtreme!

c_c

 

[True]

The Elly is PFM, so yes, your output is pulsed and the meter is just too slow to see this.

Interesting. I've tested my Elly to be about 1.2A at the tailcap with a Premium alkaline, or NiMH cell, and more like 600mA at the LED. I suspect that the current from the LED -- which cannot possibly be accurate without violating conservation of energy (1.2A * 1.2V = 1.44W in, 600mA * 3.5V = 2.1W out) Based on the brightness I've been seeing, I suspect that the input is closer to reality, and the output current is pulsed, therefore erroneous.

 

[johnny13oi]

The Elly is PFM, so yes, your output is pulsed and the meter is just too slow to see this.

How fast of a meter would you need to see this. I have a really really cheap one that takes 2.5 times a second.

 

[sparkysko]

How fast of a meter would you need to see this. I have a really really cheap one that takes 2.5 times a second.

I'd venture to guess that the pulsing is occuring in the kilohertz range. You'd likely need an oscilliscope to properly measure this. Maybe a capacitor on the output side would help? Also the voltage boosters are not 100% efficient. I'd expect this one to be 60-90% efficient. Because of this you will definetly see a lower wattage at the output than the input.

 

[Hellbore]

Hey guys

I modded one of my Cree-ized Elly to run direct drive off a 3.6v unprotected 14500 cell.

What I did was I purchased a protection circuit online so it will turn off if the voltage gets too low (3 volts I think). That way the lithium battery won't over-discharge. The protection board is tiny, it fits under the Cree star in the little cavity. I attached it with some 3M double-sided tape.

It's extremely bright, I haven't installed a limiting resistor yet so I don't know how much current it is running the LED at. I only turned it on for a few seconds. I'm thinking of using a 1 ohm resistor or something to limit the current.

Pretty cool!

 

[2xTrinity]

What I did was I purchased a protection circuit online so it will turn off if the voltage gets too low (3 volts I think). That way the lithium battery won't over-discharge. The protection board is tiny, it fits under the Cree star in the little cavity. I attached it with some 3M double-sided tape.

This is an interesting idea. Where do you buy separate protection circuits? For some of my lights, such as 1xCR123 rechargeable lights, I can go through batteries fairly quickly, so I will sometimes bring spares. Buying one protection circuit and installing it in the light will be a lot cheaper than buying tons of protected cells.

too bad such a thing probably wouldn't fit in an L0D-CE, that's probably where I could use one the most...

 

[Hellbore]

This is an interesting idea. Where do you buy separate protection circuits? For some of my lights, such as 1xCR123 rechargeable lights, I can go through batteries fairly quickly, so I will sometimes bring spares. Buying one protection circuit and installing it in the light will be a lot cheaper than buying tons of protected cells.

too bad such a thing probably wouldn't fit in an L0D-CE, that's probably where I could use one the most...

Actually, I asked earlier in this thread where to find protection circuits, and Emitter showed me this link:

http://batteryjunction.com/prcimopfor3l.html

I bought 2 of them, I used one on my Elly, I think I will use the other one on another Elly. I like how bright the Cree is at high current with the 14500 cell, I think it's bright enough to be "tactical", it's my new nighstand light. I like this setup because I can buy unprotected cells which are not only cheaper, they are actually available in higher mAh capacities than the protected cells I have found.

 

[Hellbore]

Well last night I used my Elly direct drive with 3.6v lithium cell and protection circuit. I went outside to test. Wow this thing is a THROW MONSTER. It's like a little spotlight. Hopefully I can post some pictures tonight taken of the beam on a distant palm tree or something so you can see the difference.