MJLED and X5 ??

Robocop

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After reading some newer posts I realize the newer style Inova X5 has LEDs that are easier to swap out than the older style. I have a new style and 5 of the MJLEDs that I am going to attempt to swap out.
I have seen pics of the new style circuit and it seems to have 5 resistors with one for each LED. If I do this swap can anyone tell me if I should remove the resistors to better make use of the MJLEDs higher forward voltage? If I remember correct the MJs are good to 100 mA. Can anyone give me an idea of what a factory X5 would be pushing to each LED?....with and without the resistors please...
 

wwglen

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While the MJLEDs are rated at 100mA according to testing done here at CPF they seem to start degrading when driven above 75mA.

Oh and resistance needed R = E / I = (6V-3V) / .075 = 40 ohms. You would probably be good anywhere from about 37 - 45 ohms.


wwglen
 

Robocop

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Thanks for the formula and the input however that is way over my head as far as math stuff goes. I would most likely leave the resistors in place rather than swap out any other ones.
This is what I am attempting to figure out. I do not know what the X5 would push through the LEDs with the resistors in place. If I could remove them and have maybe 80 mA or less to each MJ I think that would be a perfect match.
I know the X5 uses a 6 volt supply and that there is a certain way to wire the LEDs so that the voltage is the same for each but the amperage is divided equally to each. (forgot if it is series or parallel)
If this is right there would almost have to be some type of resistor used so with the factory resistors left in place I am curious how much mA would reach each LED.
It seems as if I have read somewhere that a member had a reading of 44mA to each LED on a factory X5. If this is correct an MJLED would make more light than the factory LEDs if both saw the same current...is that right?
I thought that was the main reason the MJLEDs sold so well was the fact the output was much greater. When I swapped one out on my Dorcy AAA I left the circuit the same. With nothing more than a LED swap output was greatly improved so I assume this X5 mod would have the same effect.
 

tvodrd

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Robo, the MJ leds were selected for low Vf to be bright on a couple AAs. They also had their lense geometry modified to work much better with the Minigag reflector. An X5 mod will require 5 higher-ohm resistors to prevent overdriving/cooking the LEDs. If you could get the unmodified LEDs, the resultant beam should be better.

Larry
 

Robocop

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Sorry however I think I may simply be saying the name of these wrong. When I say MJLED I am thinking of the 100 mA ones on the Shoppes site. It says "like the MJ" on the web site order page. I assume this is the same as the MJ however it is simply not cut down.
I have 2 of the ones from the Shoppe and 3 more on the way from a recent order. I will soon have 5 total of the un-cut versions and each capable of 100 mA. In past testing with these un-cut ones the output was nice even without any reflector at all. It did seem the LED focused much of its own light forward. I really do think if I could get 5 of these going at the same time,and under good power, it would be a great mod to have.
Larry why do you say I will need a new resistor to do this?...Have you any idea as to what current would be put to each LED if the MJ Like LEDs were swapped out?
 

tvodrd

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Robo, you will need a multi-meter to select appropriate current-limiting resistors for the X5. Buy a 25 or 50 Ohm, 5W "pot" from Digikey, and dial it in (using the current scale) for the LED current you want. Use the multimeter (Ohms) to measure the "pot" and then order the surface-mount resistors of the same value for the mod. That's the easiest way I know to do it. :shrug: Should be a bitchin' mod, If you get it right!

Larry
 
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