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Discussion Starter · #1 · (Edited)
I am having a weird problem with my light build. I have a Maxflex 3 hooked to 3 MC-E in a 2p2s setup. When I connect power [14.4V Li-ion pack, hot off the charger @ 18.47V], I get one flash from all three MC-E, then nothing. Clicks/pushes have no effect. Worse, I had everything working fine before shoving it all inside the housing. :rolleyes: Also, I don't get the flash every time I re-connect power. Any ideas? I've looked at the Maxflex documentation, but didn't see anything specific to my issue. This is driving me nuts!

Edit: I was checking my crappy soldering job, re-soldered one of the MC-E connections and was blinded. **** these things are bright. My problem now is that the light turns on with power connect but won't turn off. Time to pull the whole thing apart. Argh.
 

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Discussion Starter · #3 ·
I've noticed that MC-E #1 [in the string of three] only has two of four emitters emitting. If my battery is putting out ~18V , would the reduced load cause the Maxflex to go into direct drive?
 

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Discussion Starter · #5 ·
heatstroke said:
Each mce is wired up 2s2p ?
Then the 3 mces are wired up in series ?
So for each mce the vf is about 7V, hence 21V for the 3 mce in series ?
What is your drive current ?
The default current out of the Maxflex is 350 mA, but I don't know what current my battery discharges at. Probably 3A or something like that. With 2 die gone, the load is going to be more like 17.5V. Crap - it is in direct drive. Until such time as I can get the voltage down [or get a replacement MC-E], I won't be able to use the light normally. :madman:

Thanks for your help!
 

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It can only go into direct drive if the sum of your vf is less than your batt. Since each mce is in series (is this correct ?) then the sum of your vf is always about 3.5x2x3 = 21V. if a few die on an mce die, then only the parallel live die will see 2x the current ( so 350 mA x2).. I think your maxflex is dead, try it on something els.
 

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Discussion Starter · #8 ·
I'm really, really hoping I made a $30 mistake instead of a $60 mistake. Dies 1 and 2 on the first MC-E after the Maxflex appear dead, and they are in parallel. Dies 3,4 are good, as are the rest of the dies on the other MC-Es.

If Troutie is seeing 18.6 Vf load from 6 die, is it reasonable to assume that running 5 die in each string will result in a Vf load of 15.5V? If so, then my hot-off-the-charger battery measured @ 17.98V exceeds the Vf and the Maxflex runs in direct drive. Also, how do you kill a Maxflex? I'm under the max input voltage. I've done some horrible things to my bFlex, and it keeps coming back for more.

Yes, I am engaging in wishful thinking. Sigh. :( I have another set of three MC-E, some Boomerangs and a Maxflex coming in the next day or so, and that will hopefully allow me to see what I did wrong.
 

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yetibetty said:
Pinkrobe, is there a problem with your battery or charger? the reason I ask is because a fully charged 14.4v Li-Ion should never exeed 16.8v without damage.
I was thinking exactly the same thing. I just thought i was ignorant but am glad you brought it up Betty. As Betty said, my charger cuts out at 16.8v exactly.
 

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Discussion Starter · #11 ·
16.8V cutoff? I don't know - I measured the voltage of the pack with my multimeter, and it hit 17.6V and climbed to 17.98V in about 20 seconds. The only other time I've had to measure the voltage was when I thought the battery was dead [I forgot to plug in the charger]. It's an older pack from batteryspace.com - maybe 3 years old. I have two new packs from allbattery that I have yet to charge, but they have charge/discharge protection. I'll charge the new pack and see what happens.

Thanks for all your help thus far. I'm sure I'll need more... :D
 

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Discussion Starter · #12 ·
I got the new Maxflex wired up, as the other one was indeed toast. Expensive lesson - always make sure you know which wire is positive and which wire is negative...

I'll post up some build pics and beamshots if I get it done tonight. Currently waiting for the copper slug to be properly adhered to the Maxflex, then shorten the leads and install the optics.
 

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pinkrobe said:
I got the new Maxflex wired up, as the other one was indeed toast. Expensive lesson - always make sure you know which wire is positive and which wire is negative...

I'll post up some build pics and beamshots if I get it done tonight. Currently waiting for the copper slug to be properly adhered to the Maxflex, then shorten the leads and install the optics.
Bummer about the maxflex but happy days that it all works now. Can't wait to see the shots!
 

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Discussion Starter · #14 ·
Basement shots!
Control


The old light [Princeton Switchback 2]


MC-E on high


MC-E on low


I'll have to wait until tomorrow to get outdoor shots. The pictures didn't work out that well, as I couldn't force the exposure times on my camera. MC-E on high is pretty damn bright, much brighter than my triple Q5.

This is the light from the front:


Inside:
 

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Discussion Starter · #16 ·
OBS, you're being far too kind. True, it is bright. However, it's really, REALLY fugly. I'm going to get the Deesta housing and see how the MC-Es work in there.

Also, for anyone looking to use the EVA optic, it is easy to position, as it sits on top of the lens of the emitter. However, it's very floody, even in the narrowest half-angle configuration ["D", which is what mine is]. That works well for this build, as it is designed for commuter use, and should light up the entire roadway. In the future I would probably stick with the LM-1 and use a combination of RS and D optics.
 

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Its not that fugly looks quite smooth with the seamles tube.

what are the other 2 leds .

I have an early one of Deestas housing they are sweet and well made
I have not put anything in it but keep looking at it and wondering if it will handle 3 mce.

It will certainly do 1 mce and 2 R2s or as you may have seen from my XPE post
14 would fit in :D
 

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Discussion Starter · #20 ·
Troutie: All three LEDs are MC-E. I should be able to use Deesta's housing without worrying about overheating, since the vast majority of our after-dark riding is in temps below 5C.

msxtr: The blue goop is GE Super Blue, a heat-resistant silicone [800F].
 
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