raggie33
*the raggedier*
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it uses 3 c alkinlines now but i wanna try nihm will it be safe will it be dimmer?. flashlight is in a big maglight with a huge heatsink?
lux 3 twak safe to direct drive with 3 c nmh?
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raggie33
*the raggedier*
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cool i wasnt sure..
raggie33
*the raggedier*
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o and btw this thing is so cool. ive already put like 45 hours on it .
[ QUOTE ]
MR Bulk said:
NO!!!
[/ QUOTE ]
Did Charlie took his DD hat off recently /ubbthreads/images/graemlins/grin.gif
I tend NOT to claim to know more than the average flashaholic and certainly not more than one of our master modders - but in this case let me just say that the TWAKs I tried direct driven with 3 AA / C / D NiMhs worked prefectly nice - it certainly will depend on the Vf of the actual LS in use, care should be applied and the actual current flow measured and YMMV.
Klaus
MR Bulk said:
NO!!!
[/ QUOTE ]
Did Charlie took his DD hat off recently /ubbthreads/images/graemlins/grin.gif
I tend NOT to claim to know more than the average flashaholic and certainly not more than one of our master modders - but in this case let me just say that the TWAKs I tried direct driven with 3 AA / C / D NiMhs worked prefectly nice - it certainly will depend on the Vf of the actual LS in use, care should be applied and the actual current flow measured and YMMV.
Klaus
I have seen two Lux III's with Vf of 4.4V at 900mA. In the case of those two LED's, 3 NiMH would probably underdrive it /ubbthreads/images/graemlins/grin.gif Heck, a Li-Ion barely drove it at spec. So long answer is "it depends" (isn't this *always* the case)
My TV0K DD'd off 3 'C' 4500mah NiMh pulls 1.4a fresh of the charger. Never got the "angry blue" color, seems to run fine. I wouldn't use NiMhs DD if you have a vf of 'J' or lower. I don't see a difference in anything over 1.2-1.3a, probably just wasted energy.
EvilLithiumMan
Enlightened
This is a solid 'maybe'! /ubbthreads/images/graemlins/blush.gif You really need to know the Vf of your particular emitter. If possible, try to get a reading at 700ma and 1000ma. Or just start it out on the safe side and put in a 1/2 ohm, 1/2 watt resistor.
(OK - I know the title states 'direct drive'. But I have never been clear on whether 'direct drive' absolutlely means 'no resistor', or just means it's not 'regulated' via an up or down converter).
(OK - I know the title states 'direct drive'. But I have never been clear on whether 'direct drive' absolutlely means 'no resistor', or just means it's not 'regulated' via an up or down converter).
raggie33
*the raggedier*
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i dont wanna risk it i like the light to much.plus it runs a long time on c, alkilines anyway.but i saw some c nimh on sale localy ..but ty for all the info learning a lot.i guess 1 amp or 1000 mah is the safe level on my emiter its a lux 3 twak.
NiMH has a lower voltage (~1.3 hot off the charger) than alkies (>1.5V) and C size alkies are not as wimpy as AA's when driving current. I suspect it will work. A few hundred millivolts will make a huge difference with LED's. Also a lot of C NiMH are really AA's repackaged so you may want to check mAH capacity on those C rechargeables. If they are what I think they are, then the newer AA's NiMH actually has more balls than those Energizer C and D NiMH I see locally.
LightScene
Enlightened
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You definitely want to add some resistance before you switch to NiMh's. I'm pretty sure elektrolumens is including a resistor in the FT-3C. Take a look at the elektrolumens forum in CPF.
2 rechargeable AA's have the same capacity as one rechargeable C. Put 3 in the light and 3 in your pocket, and you'll have the same capacity at a lower cost.
2 rechargeable AA's have the same capacity as one rechargeable C. Put 3 in the light and 3 in your pocket, and you'll have the same capacity at a lower cost.
robk
Enlightened
I got several 4500mAh NiMH cells from Amondotech for $3.20 each. Can't see the savings in using AA's unless you already have them. I have about 90 AA's, but went with the higher capacity C's anyway. My FT-3C has no resistor, initial current drain is 1.4A, then settles to about an amp in 10 minutes, I hope it doesn't fry!
Rob
Rob
Doug S
Flashlight Enthusiast
[ QUOTE ]
CM said:
....and C size alkies are not as wimpy as AA's when driving current.
[/ QUOTE ]
This is a commonly held misconception that is not supported by the battery datasheets. For example, for Eveready the A93 "C" cell has an initial Ri of 324 milliohms and the A91 "AA" cell has an initial Ri of 146 milliohms. Of AA, C, and D cells, the C cells are the worst performers for terminal voltage drop at heavy loads.
CM said:
....and C size alkies are not as wimpy as AA's when driving current.
[/ QUOTE ]
This is a commonly held misconception that is not supported by the battery datasheets. For example, for Eveready the A93 "C" cell has an initial Ri of 324 milliohms and the A91 "AA" cell has an initial Ri of 146 milliohms. Of AA, C, and D cells, the C cells are the worst performers for terminal voltage drop at heavy loads.
