should my tri-luxIII mag be brighter?

i recently modded my first mag. here are the specs.

3D mag
direct drive
3 white luxIII tv1j
pts2
3 energizer 2500mAh Nimh D cells
20mm ims reflectors

the light is very bright and im very pleased with it. it has nice throw and a good amount of spill. what got me concerned was when i compared the mag with my sf e1L. the following beam shot was taken from about 4ft. i was expecting the mag to be a lot brighter than the sf. granted....the mag has much more spill than the sf....but is this typical (at this close distance)?


at further distances....the mag definitely outshines the sf.

with your bare eyes you can't really tell the differences but with a light meter, that brings it to a whole new lux lvl!

Have you checked the total current draw of your set-up?

If properly driven you ought to be getting over 200 Lumens

2500Ah D cells - sounds like old technology to me...These could be your weak point...voltage sagging too much under load.


Check current draw first and we'll have a better idea of the problem.


Tim.

get some good 10,000 mAh D cells and a "Ultra Clear Lens" also see if your Mag switch may be adding unnecessary resistance. mine (switch) was horrible till i fixed it.

Sounds like the batt's are the problem.

DUQ said:

Sounds like the batt's are the problem.

Click to expand...

a 2500MaH D battery is just a premium AA cell in a D-sized body, note how light it feels. Reminds me of my 3W Red/Orange 2AA lights...freshly-charged batteries are toast in short order. You can also have some fun w/ a hunk of PVC pipe and a different tail-cap spring and 4) "C"-sized NiMH batteries [if it's a 3D body now], though with NO resistance I dunno what the current would be, maybe ok yet, maybe not.

i used the D batteries because they were one of the options that Mod-a-mog listed in his tutorial. i guess i could try some better D batteries....or try some AAs. thanks for everyone's input.

here is what mod-a-mag wrote:

Tri-Star Direct Drive Configuration (resistor may be necessary depending on Luxeon bin & drive level)
Mag1C - 1x17500|18500|17650|18650 Li-Ion - Luxeon in parallel
Mag1D - 3|4x14500 Li-Ion parallel - Luxeon in parallel *
Mag1D - 3|4xAA NiMh in series - Luxeon in parallel *
Mag2D - 3xC NiMh - Luxeon in parallel *
Mag2D - 8xAA NiMh in series - Luxeon in series *
Mag3C - 3xC NiMh - Luxeon in parallel
Mag3D - 3xD NiMh - Luxeon in parallel
Mag4C - 4xC NiMh - Luxeon in parallel
Mag4D - 4xD NiMh - Luxeon in parallel

Click to expand...

With those cells and a parallel configuration I'd be surprised if you're getting much more than 200-300 Ma per emitter.

Even with top D cells I wouldn't think you'd get much more than 500Ma each

You could try 3 x D Alkaline cells - but these may not be up to the current draw


You might try what kd9uu suggested and put in 4 decent NiMh 'C' cells.

I'd throw in a 0.5 Ohm resistor just to temper things a little (About 6W should do)

You can always take it out if you're not getting the current you want - But I recon you ought to be getting around 1A per emitter with this configuration - put probably less when you factor in the inherrant resistance from switch / contacts etc within the flashlight.

But bear in mind that your Lux's Vf will drop with use - so current to emitters will rise as they age


Tim.

Good 10,000mah NiMH D's is what you need. Those you have now are low capacity, and sagging under load since the luxeons want to pull 3+ amps from them. The runtime if they could do that would be way under a hour.

If you get good NiMH d's, then you will likely need resistance, as J is a little too low for NiMH unless you don't run them hot off the charger. K is bet best bet. How much resistance to bring it to more like K vf, I'm not sure. Someone else might chime in?

It's your batteries... Try to measure current with the tail cap removed and report back...

Another option is to stuff 4 alkaline C's in there. That's more than enough voltage to the luxeons, but since alkalines can't sustain the current their voltage will sag and they will self limit themselves. Don't do 4 NiMH or your luxeons will fry.

My Electrolumens Tri-star Phazer runs 3 parallel J bin LuxIII's from 4 x 4500Mah NiMh C cells

The cells unloaded measure 5.2V.
Total current drawn is 2.1A (700Ma per emitter)
Looks like wayne put a 1 Ohm resistor in series with each emitter.

I think a Maglite conversion will have more internal resistance than the Tri-Star Phazer

So there you go - 4 C cells are OK to use - But as IsacHayes correctly states - not without added resistance or the Lux's will die.

0.5 Ohms resistance will definitely be overdrive
.75 Ohms ought to drive your Lux's around spec in a Mag
1.0 Ohms will be under driving your Lux's


Tim.

what do you guys think of this.

how about i switch the head to my 2D body and use 8AA 2500mAh Nimh in series(energizers)....and the LUXs in series. do you guys think that this would work better?

im definitely going to use a driver for my next project.

on another note....this light is pretty bright already, i cant wait for it work correctly!!

Try throwing some alkalines in and see what happens. I have a Tri lux3 3x TXOJ wired parallel on 3C batteries in a 2D mag. This light will pull 2.4 amps from the batteries, which places them right at spec.

Kal El in SLO said:

how about i switch the head to my 2D body and use 8AA 2500mAh Nimh in series(energizers)....and the LUXs in series.

Click to expand...

I recon that would be a pretty good solution. Should draw around 1A on fresh Nimh AA's


Tim.