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Discussion Starter · #1 ·
Could use a little help :)

I'm familiar with building lights, and I have a few triple Q5 lights, but now I wan't to make a shot at building a dual MC-E light

I have a spare 3032 wired buckpuck 1000 Ma and a 14,8 battery pack. So how do I get the most of it and how should I wire the MC-E's - an illustration would be great as 2p2s doesn't make much sense to me :D

Thanks in advance
 

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That configuration(1000 ma buck puck) is exactly what achesalot used for his light. http://forums.mtbr.com/showthread.php?t=476362

Seems like everyone who has tried it has been able to run the 4 LEDs in series using a 14.8V LIion battery.

The only down side of using the 1000ma buck puck across two 4 led strands(500 ma each) is that you can't get them to the max 700 ma ratings.

Have fun.
 

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texas said:
That configuration(1000 ma buck puck) is exactly what achesalot used for his light. http://forums.mtbr.com/showthread.php?t=476362

Seems like everyone who has tried it has been able to run the 4 LEDs in series using a 14.8V LIion battery.

The only down side of using the 1000ma buck puck across two 4 led strands(500 ma each) is that you can't get them to the max 700 ma ratings.

Have fun.
You have two options for a twin MCE and a 14.8v bat. You can get series wired stars and run them on two string - so each string is in parallel, or you can wire the stars 2s2p and then run them in series. Ultimately, I don't know that it makes much difference.

I bought my MCE's on a series wired star (from cutter) for the duster and as TEX said, was able to run it off a 14.8v bat using a buckpuck. I expect it will dim as the battery voltage drops into the 12's but i haven't been on a ride long enough to find out yet.

So far it looks like the ledil boom optics are the winners... they are still very floody but less so than most MCE optics
 

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ocean breathes salty said:
You have two options for a twin MCE and a 14.8v bat. You can get series wired stars and run them on two string - so each string is in parallel, or you can wire the stars 2s2p and then run them in series. Ultimately, I don't know that it makes much difference.
These 2 configurations will result in the same current to each light. so the result should be the same. 4 in series is a bit simpler to wire since each contact on the star only gets one wire. Or better yet if you have not ordered your MCE yet just order the star with all 4 in series.
 

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@ Tex... There was intially a lot of talk about imbalance in the strings causing problems. So I wasn't sure which way would minimize this. Relying on two different MCE's to have the same Vf or relying on the individual dies within the MCE to have the same Vf. In the real world it probably doesn't matter i guess

@ Trout... I know the hipflex is one big mofo of a driver but how will it go dropping the vf from a 14.8v battery (the OP's battery of choice) to the 3.x output needed for 4p 2.8A?? That is a large voltage discrepancy and I will be interested to see how it copes thermally. I would be interested to hear georges take on it.
 

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Those boards will most certainly blow up if driven from 14.8V, even with a resistor. This is because of the switching nature of this type of driver.
You can use the same principles for serial/paralell wiring of the led as you use for the stars. Think of the individual dies in the MC-E as individual stars.

If you are thinking of buying a different driver than your buckpuck to get more than 500mA into your MC-E:
The blue shark bwilli linked to is really good and easy to use (except the tiny solder pads) Just wire all i series.
This cheap driver also works well, but you will need to adjust the output with a resistor or potentiometer and use one for each led.
 

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Froberg said:
Thanks for the answers.
I'm getting a little bit confused about all the serial/parallel wiring of the LED - I know how to make the stars serial/parallel :)

I've got a few of these lying around, maybe thats an even better choise to make one drive each LED, and then use a resistor ?

https://www.dealextreme.com/details.dx/sku.3256
Just some simple diagrams that might help you get your head around it all...

bear in mind that you can buy the MCE's on stars which have all the below wiring pre-done.

see here (half way down the page)







Hope this helps in some way
 

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Discussion Starter · #12 ·
Great illustrations - that's just what I needed, thanks !

Ok, so I'm slowly getting there....
I think I have to go for the 2s2p so I don't fry the LED's - as far as I know 1000 Ma is to much for them - so 500 Ma should be the right way to do it.

Putting the stars in series, I guess the red line should go to the black line on the next star ?
 

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Froberg said:
Putting the stars in series, I guess the red line should go to the black line on the next star ?
Sorta. Yes, that will work, but your Vf will be 6.2 V for one MCE, but when you add the second you will be back up to 12.4V (i.e the same as a series wired MCE)

So you don't really gain any driver overhead with your 14.4v battery doing it that way. If you are going to be stuck with 12.4Vf then it might be easier to just get the series wired stars.

This is how i wired my 2 MCE's off a 1A puck and it is running fine off a 14.8v so far. Although i haven't dropped the battery voltage far enough to see what happens when it goes direct direct drive yet.

switch diagram is courtesy of citizen kain

 

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Salty says: Serial stars seriously simplifies soldering, sketched sweet setup saves some sweat.

Well...that spaghetti tangle looks easy enough. Haha, just joking. Nice colours!

It's totally correct. Much less soldering with prewired stars. If you want to practice soldering -don't do it on $25 leds...
 

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gillestugan said:
Salty says: Serial stars seriously simplifies soldering, sketched sweet setup saves some sweat.

Well...that spaghetti tangle looks easy enough. Haha, just joking. Nice colours!

It's totally correct. Much less soldering with prewired stars. If you want to practice soldering -don't do it on $25 leds...
It does look a little bit like a pasta meal doesn't it :D It doesn't look anywhere near as bad if you just use a 3023 with external pot instead of the switch... Then it is super simple.

I find Hi/Lo concept more user friendly than the infinitely variable pot, some times it is possible to have too many options and then you spend more time fiddling with the pot that you do looking where you are going!
 
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