1D lights?

[flatline]

Well, I broke down yesterday at Home Depot and spent $2.98 on an Eveready 1D plastic light. Same size as the 2D basically, but with a giant spring and a pedestal inside for lack of a better word to stop the battery from dropping in further than intended. Plastic lens, stippled plastic reflector, the switch action is suprisingly decent. Tailstands, has anti-roll, and is very lightweight. About twice as bright as my E01, I'm going to do a runtime test on it. I'm sure it's not regulated, and it will dim over time. EVE3151 is the model number. Mine's a spiffy red one. I came close to getting the 2-pack for $5.00, but they're not flying off the shelves and I figured there may be a few left if it seems decent...

That's a pretty typical price for a 2-pack around here both at Kroger (grocery store) and the various hardware stores (Home Depot, Lowes, etc).

The current 1D model is better than the previous model that used a PR-bulb since the battery would eventually smash in the bottom of the PR-bulb and it would no longer make an electrical connection. I'm still waiting to see if the current 1D model will out live the battery it was sold with.

Edit: Whoops! I guess I'm a generation behind. I just saw what you're talking about at Target with a real LED and a reflector rather than a 5mm LED and an optic. 2-pack was $6. Switch is the same as the previous generation, but everything else is better (brighter, beautiful beam, nice tint). I'm actually really impressed with these.

--flatline

 

[scout24]

80 hours and still going strong. I did toss the oem battery and install a Duracell alkaline before starting. It has dimmed, and is E01-on-a-fresh-cell bright right now. And the E01 makes the tint look awesome.

 

[scout24]

9am today was 120 hours. Still comprable to a fresh E01, and still going strong.

 

[lampeDépêche]

The capacity of a D-cell is more than 10 times that of an AAA cell.

Eveready says that at a constant draw of 25ma, their AAA cell will give about 1100 mah, their D cell about 17,000mah.

I'd say you are going to be giving us updates for several weeks, Scout!

 

[WalkIntoTheLight]

Yes, D's have an insane amount of capacity if drained very slowly. Up to 25,000 mAh if the current is a trickle. But you'd only get that with a battery-vampire light, and most flashlights that take D cells drain them far too quickly to get the benefit of the high capacity. IMO, D-cell lights don't serve much purpose anymore, since with LEDs you can get long run time with AA's. When I was a kid, all we ever had were D cell lights (or their 6-volt block equivalent), but of course they used incandescent bulbs.

 

[xxo]

9am today was 120 hours. Still comprable to a fresh E01, and still going strong.

Pretty impressive run time!

I have one of the Eveready 1D's and I like that it, unlike most of the 2 cell Eveready LEDs, is not direct drive and will run brightly on Eneloops in adapters or nearly depleted cells. I wanted to see if this light would run on C cells and I pulled a dead alkaline C cell from the recycle bin and dropped it in was surprised not only that it lit right up but was fairly bright on a "dead" alkaline C. The spring pressure is enough to hold C cells in place with no rattle. The ability to run on single near dead D or C cells (and even AA's with an adapter) might come in handy during an extended power outage.

 

[flatline]

I wanted to see if this light would run on C cells and I pulled a dead alkaline C cell from the recycle bin and dropped it in was surprised not only that it lit right up but was fairly bright on a "dead" alkaline C.

That is excellent news. I was hoping that these would do well with scavenged batteries.

Has anyone bothered to measure the current draw on these yet?

Edit: I found my multimeter and it looks like the Eveready 1D flashlight draws about 160mA from a fresh D cell. I only ran it for about 10 seconds before taking my reading. I don't really know what the best practice is.

--flatline

 

[Lynx_Arc]

That is excellent news. I was hoping that these would do well with scavenged batteries.

Has anyone bothered to measure the current draw on these yet?

Edit: I found my multimeter and it looks like the Eveready 1D flashlight draws about 160mA from a fresh D cell. I only ran it for about 10 seconds before taking my reading. I don't really know what the best practice is.

--flatline

The best practice is what you did if you have a digital meter you may try the 10A scale using the shunt in the meter it will give you a higher reading usually if not out of range (too low for the setting). An interesting thing to do is to have 2 meters and a variable resistor and use the variable resistor to drop the voltage to your LED circuit and see how low of voltage and current drive and light output can get before it is no longer useful. This will help determine how far it can drain batteries in use before they are no longer useable. Some 1 cell boost circuits can supply workable light output down to close to half a volt (0.5v) input but in reality if you can get it to work down to 0.7v that will have the battery pretty much all used up beyond 95% totally depleted I'm guessing.

 

[lampeDépêche]

The best practice is what you did if you have a digital meter you may try the 10A scale using the shunt in the meter it will give you a higher reading usually if not out of range (too low for the setting). An interesting thing to do is to have 2 meters and a variable resistor and use the variable resistor to drop the voltage to your LED circuit and see how low of voltage and current drive and light output can get before it is no longer useful. This will help determine how far it can drain batteries in use before they are no longer useable. Some 1 cell boost circuits can supply workable light output down to close to half a volt (0.5v) input but in reality if you can get it to work down to 0.7v that will have the battery pretty much all used up beyond 95% totally depleted I'm guessing.

That's interesting stuff, Lynx Arc, and it tells me that you know more about electronics than I do. (I don't know much).

Suppose I get one of these low-price Eveready 1D set-ups. If I drop a relatively fresh cell in there, it will put out about 9 lumens at the start (or as Scout says, about an E01 output), do that for 120+ hours. Then at some point it will start dropping to lower outputs.

Here's a question for you: if I put a resistor in between the cell and the circuit, could I get it to produce lower output from the start, and last longer?

For my purposes, I would rather have 1-lumen output for 900 hours than 9 lumens for 100 hours.

The things I don't know are:
1) will the circuit still work with a resistor between it and the cell? (But your post makes me think, "yes! it will!" at least for some ohm-values.)
2) will this use up the battery more slowly, or just waste power in the resistor?
3) what sort of ohm-ranges should I be playing with?

Like I said, I don't know much about electronics, but Radio Shack did not make you pass a test before selling you goods, so I have a bag of all kinds of resistors at home. I was thinking of buying one of these lights and just doing some trial-and-error with different ohm-values.

I will still do that, but if you know of calculations that would put me in the right ball-park, that could save me some time. Also, if power-wastage through the resistor is an issue, then maybe it's not worth it--I don't want to trade 100 hours of 9 lumens for 100 hours of 1 lumen, i.e. reduce the output and not get any longer runtime.

 

[TinderBox (UK)]

Below is a link to an Energizer alkaline d cell, It give you capacity at various loads.

http://data.energizer.com/PDFs/E95.pdf

John.

 

[Lynx_Arc]

That's interesting stuff, Lynx Arc, and it tells me that you know more about electronics than I do. (I don't know much).

Suppose I get one of these low-price Eveready 1D set-ups. If I drop a relatively fresh cell in there, it will put out about 9 lumens at the start (or as Scout says, about an E01 output), do that for 120+ hours. Then at some point it will start dropping to lower outputs.

Here's a question for you: if I put a resistor in between the cell and the circuit, could I get it to produce lower output from the start, and last longer?

For my purposes, I would rather have 1-lumen output for 900 hours than 9 lumens for 100 hours.

The things I don't know are:
1) will the circuit still work with a resistor between it and the cell? (But your post makes me think, "yes! it will!" at least for some ohm-values.)
2) will this use up the battery more slowly, or just waste power in the resistor?
3) what sort of ohm-ranges should I be playing with?

Like I said, I don't know much about electronics, but Radio Shack did not make you pass a test before selling you goods, so I have a bag of all kinds of resistors at home. I was thinking of buying one of these lights and just doing some trial-and-error with different ohm-values.

I will still do that, but if you know of calculations that would put me in the right ball-park, that could save me some time. Also, if power-wastage through the resistor is an issue, then maybe it's not worth it--I don't want to trade 100 hours of 9 lumens for 100 hours of 1 lumen, i.e. reduce the output and not get any longer runtime.

Depending on the circuit most likely it would drop the output and lower the current used depending on the resistor used. If your measure of 160ma at 1.5vdc is about 9 lumens then about 20ma or so should give you in the 1-2 lumen range I'm guessing. I can only guess than about 1v into the circuit would give you a start that means about 0.5vdc voltage drop at 20ma R=E/I so 0.5v/0.020A = 25 ohms. This would be a start put the resistor inline and measure the current and eyeball the resulting output and adjust the resistor higher for lower output etc. Assuming this value is correct the power "wasted" would be about 10mw vs 240mw used at the 9 lumen output and the resulting power usage would be 30mw total so you wast about 1/24th of the power at the normal output to drop the total usage to 1/8 the power used making for 23/24ths power "not wasted" at the lower output. I think I got this math right?

 

[lampeDépêche]

That's a huge help, Lynx Arc! Thanks so much for writing it out.

I did not understand all of the details, but I think I understood this much as answers to my questions:
1) I should be able to run the circuit with a resistor between the cell and the circuit.
2) It will reduce the light-output, and it will extend the run-time, and it will waste some power. But the waste is probably not a huge waste.
3) I should play around, but 25 ohms is a plausible value to start with, and then I can go up and down from there and see what I like.

Here's how I understand the power-wastage issue. I'm going to talk this through like I'm stupid, because I'm ignorant, and you can correct me where I'm wrong.

If the resistor did not waste any power, then it would increase run-time by the same factor that it decreased output. As a result, the product of (output x runtime) would remain constant. If it gave me 24 hours of 10-lumen light without the resistor, then it would give me 240 hours of 1-lumen light with the resistor (all numbers just for example).

Because there is power-wastage, the integral or product will not be constant. Instead of 240 hours, I might get 230 hours of 1-lumen light.

If that is right, then it is a trade that I am willing to make. I would rather get the longer runtime. In addition, I suppose that at some point in the cell's life, I can take the resistor out of the circuit and use up the remaining portion of the cell without that wastage from the resistor.

Okay, I will definitely try this out and play with it, now that I know roughly what results I am likely to see.

 

[flashy bazook]

The appeal is that I have a stash of partially used C and D cells that I can only use in a single cell flashlight since I have no way of reliably matching them in pairs or triplets. If I had a 1D light that I liked using, I could burn through all those cells with that light.

--flatline

You could use 1xD in a 2xD flashlight (or 3xD...) by using a dummy D-cell.

So you can have the possibility of using the more powerful 2xD, 3xD, etc. flashlights when you can match the batteries, or use them as 1xD if you cannot.

Of course this assumes the flashlight has the voltage range, plus you don't mind carrying around a bigger/heavier flashlight.

 

[Lynx_Arc]

That's a huge help, Lynx Arc! Thanks so much for writing it out.

I did not understand all of the details, but I think I understood this much as answers to my questions:
1) I should be able to run the circuit with a resistor between the cell and the circuit.
2) It will reduce the light-output, and it will extend the run-time, and it will waste some power. But the waste is probably not a huge waste.
3) I should play around, but 25 ohms is a plausible value to start with, and then I can go up and down from there and see what I like.

Here's how I understand the power-wastage issue. I'm going to talk this through like I'm stupid, because I'm ignorant, and you can correct me where I'm wrong.

If the resistor did not waste any power, then it would increase run-time by the same factor that it decreased output. As a result, the product of (output x runtime) would remain constant. If it gave me 24 hours of 10-lumen light without the resistor, then it would give me 240 hours of 1-lumen light with the resistor (all numbers just for example).

Because there is power-wastage, the integral or product will not be constant. Instead of 240 hours, I might get 230 hours of 1-lumen light.

If that is right, then it is a trade that I am willing to make. I would rather get the longer runtime. In addition, I suppose that at some point in the cell's life, I can take the resistor out of the circuit and use up the remaining portion of the cell without that wastage from the resistor.

Okay, I will definitely try this out and play with it, now that I know roughly what results I am likely to see.

Pretty much the case as a resistor always uses some power but by dropping the overall power used you get longer useful runtime instead of being brighter than you need for 24 hours you get just the right brightness for the 230 hours. Now in use the numbers I gave will probably not turn out the same as LEDs often get more efficient at lower current driven levels but on the flip side circuitry can be designed such that they are or aren't more efficient at lower current levels some circuitry has regulation of sorts that as voltage declines the current is increased to try and keep power levels the same. I seriously doubt such a cheap light would have but a simple boost circuit in it that should operate as expected. The only thing that does concern me since I don't have the light to test things is the circuit could be designed such that it doesn't operate well as the voltage from the battery (source) drops below 1.1v or so. I've seen several boost design circuits that just won't drain that final ~10% (or less) of the power from depleted alkalines etc that under a load when they reach the last of the power they have left cave in voltage too low to power up a circuit that demands too high of a current and you get either blinking or a light that runs for a very short while and shuts off and waiting for awhile and turning it back on again yields the same very short burst of light then.. nothing.
One thing I've done in the past to eek out that last little bit of power from alkalines is when a single battery won't power the LED get two of these batteries that don't have enough power and wire them in series and connect them and then you have enough power. Usually such batteries cave under a load such that even what you would consider double the voltage doesn't bring you back to even the original output of the light as 2 batteries that measure 1.1v not under a load and 2.2v combined not under a load when hooked to the circuit drop to 1.2v (or less) under the load.
Another thing also is if you checked out the Energizer D cell data link posted by another here you will realize that as the current load on the battery drops you get MORE power out of the battery (in total) so dropping from 9 lumens to 1 lumen the slight loss in power due to the resistor may actually be made up by increased capacity of the battery at the lower power draw level.

 

[flatline]

Burn em up as lanterns using AAA and AA lights... your Quark can do it (any battery chem/size).

I've been giving this some consideration. I could rig up something with PVC and a night light topper. My Quark AA is already doing night light duty when the power goes out (moonlight mode should be able to get multiple months of continuous runtime out of some ER14505 cells that someone was going to throw away at work).

Quite frankly, I had forgotten that I could remove the Quark head from the body...

--flatline

 

[xxo]

That's interesting stuff, Lynx Arc, and it tells me that you know more about electronics than I do. (I don't know much).

Suppose I get one of these low-price Eveready 1D set-ups. If I drop a relatively fresh cell in there, it will put out about 9 lumens at the start (or as Scout says, about an E01 output), do that for 120+ hours. Then at some point it will start dropping to lower outputs.

I think the current Eveready 1D version is listed as 25 lumens, which seems about right but the tint on mine sucks, very blueberry colored. I guess you get what you pay for on this one in build quality, output and tint.....after all it's a $3 plastic flashlight! The ability to vampire single D and C alkaline cells and run on AA eneloops in adapters is what makes it interesting to me.

 

[eh4]

Any single AA or AAA light that has a head which unscrews from the battery tube should be very easy to adapt to a D cell.
L3 Illumination L10, L11, or L8 would make nice D cell lights with their 3 or 4 (+firefly) modes...

With 2+ decades of old single cell twisties out there,
there's lots and lots and lots of options.

Also the Nite Ize 2-6 cell PR flange led conversion bulb runs a lot dimmer and longer on a single cell than on the 2-6 cells (3-9v) that it's marketer for, they're a bit pricy for how far the tech has come, but only weighing a few grams each, if you had two of them you could always wire up light no matter what battery was available from .9v to 18v....

 

[flatline]

I took an AA with .98v open circuit voltage and was able to get useable steady output from the latest generation Eveready 1D flashlight. The current draw after 10 seconds of operation was about 21mA.

For comparison, the same battery would cause the LED from the first generation 1D flashlight (PR bulb with slider switch) to flicker, but not produce useful light.

How far down does a flashlight need to be able to pull a battery to be considered a battery vampire?

--flatline

 

[Lynx_Arc]

I took an AA with .98v open circuit voltage and was able to get useable steady output from the latest generation Eveready 1D flashlight. The current draw after 10 seconds of operation was about 21mA.

For comparison, the same battery would cause the LED from the first generation 1D flashlight (PR bulb with slider switch) to flicker, but not produce useful light.

How far down does a flashlight need to be able to pull a battery to be considered a battery vampire?

--flatline

There is no set amount of low voltage operation to consider a light to be a battery vampire but typically if a light will operate to less than 0.9v on a 1.5v battery it has pretty much sucked perhaps 98% (or more) of the useful battery power out of the cell. If the light is bright enough at ~1v then it probably will drain it down to 0.8v or lower before the output isn't much useful.

 

[flatline]

There is no set amount of low voltage operation to consider a light to be a battery vampire but typically if a light will operate to less than 0.9v on a 1.5v battery it has pretty much sucked perhaps 98% (or more) of the useful battery power out of the cell. If the light is bright enough at ~1v then it probably will drain it down to 0.8v or lower before the output isn't much useful.

In that case, these lights do a pretty good job getting every last bit of juice out of the battery.

I just finished a walk outside with the kids. At the end of the walk, the spill was still bright enough that I could use it to avoid tripping on sticks. Open circuit voltage of the cell just measured 0.92v. The LED is dim, but still bright enough to be uncomfortable to look at directly. I expect it to die shortly.

All in all, for $3, I'm pretty impressed. Decent beam, excellent run time, sufficient light for most purposes, and to top it off, I just got 2 hours of walk out of a battery that I pulled out of a Wii Remote that wouldn't even power up enough to complain about having dead batteries.

Edit: I just compared to my Quark's moonlight mode (0.2L) and the 1D is still well above that. Even though the battery is now below 0.9v.

--flatline