GlowBox Emergency Lantern (or at least, that's what I'm calling it!)

Ingredients:

One knockoff Pelican case, with transparent lid.
Two 2S AA battery carriers
One Two-way switch
13 Warm White 5mm LEDs
One "breadboard"

and a whole lot of dodgy soldering and a metric buttload of Hot Glue :devil:

I had an idea for a waterproof, drop-proof, super runtime, barn-door engineered emergency lantern. Essentially, assemble all of the listed bits into the listed box, and presto!

I present the GlowBox!




The two-way switch swaps between 12 LED's and One LED. The batteries are 2S2P, for 4000mAh on eneloops. I'm guessing, many, many hours of runtime on low, and a not-unrespectable runtime on high. (Also, I have since cleaned the lid!)

On Low:



On High:


The battery carrier comes out to make swapping easer. It just happens to be a perfect press-fit when the lid is closed, and doesn't move at all, no matter how hard I shake the box.



Lid Closed, on High:



The Low LED, and one of the High LED's shine through the clear (dirty in the photos, ) part of the lid. This helps Low be a little bit more useful, and on High you can actually navigate with it. I made it around the back yard without falling over anything with it on high .

I'm pretty happy with it, and it'd be a properly useful camping lantern, if nothing else.

Now add a diode to each side of the batteries, install rechargeable batteries, add plug and charge. Good job though bud. See ya around.

Since no one cares... On low it's managed 500 hours and is still going strong.

I love these kinds of builds, and the GlowBox is definitely a diamond in the rough. All it needs is a slightly better electrical scheme to be great.

If all it's able to do on high is keep you from killing yourself in the back yard, I'd suggest 3S for the supply voltage, and an appropriate resistor on each switch position. Keep the 4 space holder for the snug fit, but wire it to only use three batts. You should be able to get around plenty well on low with around 25ma to the single LED. On high, calculate for say, 15ma to each LED on fresh batts, and you could lead a small group out of the back yard without mass casualties.

Slightly less "efficient" per se, but much more useful, and it still retains it's barn-door engineering!

I think it would be great to have in a tent. Nice job.

Thanks for the advice but since the goal was runtime over brightness, I wanted to avoid having to use a resistor as it is just turning my precious power into heat.

The LED's, very conveniently, seem to cut out at 1.9V, so the eneloops never drop below 0.8V meaning I can run it until it dies without worrying about killing my batteries

I might start a pool on how long it will run

The batteries measured 1.45V at the start of the runtime test.

It's just ticked over 612 hours (25.5 days) without being turned off, and the batteries measure 1.31V.

Any guesses how long it'll last?

what voltage are you feeding the LED's? how are they wired, series, parallel, combo?

Mylt1 said:

what voltage are you feeding the LED's? how are they wired, series, parallel, combo?

Click to expand...

Low is a direct connection to the 2S2P battery pack.

High is 12 LED's in parallel to the battery pack.

mvyrmnd said:

I might start a pool on how long it will run

The batteries measured 1.45V at the start of the runtime test.

It's just ticked over 612 hours (25.5 days) without being turned off, and the batteries measure 1.31V.

Any guesses how long it'll last?

Click to expand...

running direct drive off 2 nimh cells it will run for probably months depending on how dim is acceptable to you. I have a few 2AA or 2AAA incan lights modded with cree 5mm wide angle LEDs (reflectored) and they are able to put out usable light for about a month or so off 2AAA and 6 weeks or so off 2AAs as the LEDs are pretty efficient and will produce light down to a fraction of a milliampere.

mvyrmnd said:

Low is a direct connection to the 2S2P battery pack.

High is 12 LED's in parallel to the battery pack.

Click to expand...

what is the voltage of the LED's, 3v or 3.5? i have some 5 and 10mm LED's im wanting to use and figured i would use the 5mm as a "low" setting and the 10mm for the "high". i also have some 3.2v XP-E's to use which im going to run off some 3.2v batteries i have. any reason you with with AA's instead of something like 18650's?

OH, and thanks for your help. i posted about needing help setting up an emergency light box and didnt get any post. seems everyone here is only interested in flashlights.

Mylt1 said:

what is the voltage of the LED's, 3v or 3.5? i have some 5 and 10mm LED's im wanting to use and figured i would use the 5mm as a "low" setting and the 10mm for the "high". i also have some 3.2v XP-E's to use which im going to run off some 3.2v batteries i have. any reason you with with AA's instead of something like 18650's?

OH, and thanks for your help. i posted about needing help setting up an emergency light box and didnt get any post. seems everyone here is only interested in flashlights.

Click to expand...

The average 5mm LED has a vf between 3.4 and 3.6 but that is the voltage at which they will operate at 20ms (normal). If your 10mm and cree LEDs have the same Vf then they will probably put out close to the same amount of light at lower voltages and currents also. The only reason I see for mixing LED types is type of light output. If I was you I would try the XP-Es running off low voltage you will find they output about the same or better than 5mm LEDs if you can account for the beam angles etc.

Lynx_Arc said:

The average 5mm LED has a vf between 3.4 and 3.6 but that is the voltage at which they will operate at 20ms (normal). If your 10mm and cree LEDs have the same Vf then they will probably put out close to the same amount of light at lower voltages and currents also. The only reason I see for mixing LED types is type of light output. If I was you I would try the XP-Es running off low voltage you will find they output about the same or better than 5mm LEDs if you can account for the beam angles etc.

Click to expand...

the 5mm and 10mm LED's will be in one box and the XP-E's will be in a different box. im still not set on the power source for each box but thinking 18650's for the 5/10mm LED's and the 3.2v batteries i have for the XP-E's. or, i may make 3 different boxes with the 5mm, 10mm, and the XP-E's all in there own boxes with different power sources for each. i have a solar charger for the 3.2v batteries i have but need to mod a charger for the 18650's. my only problem is figuring out what i need to regulate the mAh's to the LED's or if i should just direct drive and let things run there course.

Mylt1 said:

the 5mm and 10mm LED's will be in one box and the XP-E's will be in a different box. im still not set on the power source for each box but thinking 18650's for the 5/10mm LED's and the 3.2v batteries i have for the XP-E's. or, i may make 3 different boxes with the 5mm, 10mm, and the XP-E's all in there own boxes with different power sources for each. i have a solar charger for the 3.2v batteries i have but need to mod a charger for the 18650's. my only problem is figuring out what i need to regulate the mAh's to the LED's or if i should just direct drive and let things run there course.

Click to expand...

You could regulate the power using the 18650s but with the 3.2 starting voltage you don't really have any overhead to run a regulator that would be worth it.. a resistor solution is probably best to limit current and the efficiency is probably for practical purposed the same as a regulated solution IMO. The advantage of direct drive is at voltages lower than the Vf of LEDs they run at lower currents than the LED is rated. A 5mm LED rated at 3.4v 20ma would probably run around 15 ma off 3.2v while an LED that is rated at 350ma at 3.4v would run perhaps around 250-300 or so ma. using direct drive with rechargeable batteries if you need more light output you add LEDs if you need less you subtract LEDs, use a lower power LED, or a resistor.

thanks for the help. im going to start design/construction this weekend if i can get some battery holders and mod them by then.

very nice mod, quite creative imo

Heh, this is great, I love mods like this.... makes me want to come up with something like it

Very nice mod...inspiring me to build something like this for my next snow camping trip down your way in July. I've got the ridiculous floodies already going (well they were until I tore them apart in search for MORE POWER!) but something like this for inside the tent would be super practical.

Like I don't have enough projects already :-(

So much for being an emergency lantern... My 2yo had just adopted it as his nightlight!

I have two alkaline D cells hooked to a 10k potentiometer and one white 5mm LED (Cone-tip optics for area light). It gives enough light on 'high' to navigate stairs after walking inside during the day, and the 'dim' is a good walking-at-night-inside light. Still too bright on low for night-light use in my mind.