Results 1 to 20 of 20
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124

    Driver Board for Old Marwi Housing

    Hi,

    I have been direct driving my P7 LED for about a year now with two 18650's and recently it started acting up. It seems that when I test with the battery (a single 18650) on a full charge the LED will only run for a second before shutting off. On a partially drained battery it runs fine. I am assuming that since the batteries charge up-to 4.2v, that over time the LED has become sensitive to the extra voltage.

    I ordered a new LED but I was wondering if any of you know of a driver/limiter board that I could use that would fit inside the Marwi housing (or any other solution)? I bought one from dealextreme last year but it was too large to fit.

    Thanks,

    David

  2. #2
    mtbr member
    Reputation: troutie-mtb's Avatar
    Join Date
    Sep 2007
    Posts
    3,043
    For all things Marwi try here

    el32 off these forums

  3. #3
    mtbr member
    Reputation:
    Join Date
    Sep 2010
    Posts
    150
    Yes, EL32 has got everything, including instructions here.

  4. #4
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    I have been all over that site. I have even purchased stuff from there. His set required soldering two 1400mA boards together. I was wondering if there was a simpler way.. He's out of stock on the driver boards for the XML which look like they could work for the P7 too.

    David

  5. #5
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    can I wire a driver board into the battery pack? if so I can just use the driver I have, that doesn't fit in the housing. Seems like it should work.
    Last edited by djonesax; 03-22-2012 at 11:24 AM.

  6. #6
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    After tearing apart my light now im not so sure it's an LED issue.

    The same batteries that were not fully charged that worked in the light, also work with a full charge after charging them all night. But both of my original batteries that I use for the light (that also have a full charge) only power the light for half a second. BUT they work properly in my SSC P7 LED flashlight.

    I looks to me like a battery issue now, but why would they work in the flash light and not for the LED in the Marwi? Maybe one LED is drawing more current?

  7. #7
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    I bought two of these guys anyway... They seem to be the same or similar, to what EL32 uses.

    $4.2 | AMC7135*8 2800mAh 1-Mode Circuit Board For SSC P7,MUC,SST-50 Worldwide Free Shipping!!!

  8. #8
    mtbr member
    Reputation:
    Join Date
    Apr 2010
    Posts
    488
    El34!

  9. #9
    Carbon8er
    Reputation: El34's Avatar
    Join Date
    Jan 2009
    Posts
    1,130
    That 2800 multi mode board has been great so far, but I don't have enough of them to sell.

    KD stopped selling them but there is a couple threads here somewhere and one of them has a link to another supplier.

    There are different versions out there but the 105C boards are the ones I like

    Search for the threads that have the words 2800 ma in them or 105C

  10. #10
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    Quote Originally Posted by El34 View Post
    That 2800 multi mode board has been great so far, but I don't have enough of them to sell.

    KD stopped selling them but there is a couple threads here somewhere and one of them has a link to another supplier.

    There are different versions out there but the 105C boards are the ones I like

    Search for the threads that have the words 2800 ma in them or 105C
    I managed to find a similar board listed as 1 mode. If it works as promised, I actually prefer 1 mode anyway.

    What do you think about my last comment. Its a very strange issue and I'd love your feed back.

    Basically what it boils down to, is that I have two batteries with a full charge and the LED only lights up for a half a second then right off. These batteries work in my simple P7 LED flashlight. I have two more batteries, that on a full charge will power the LED just fine with out shutting off. very weird. Seems unlikely that I have two bad batteries but the LED works with the other two batteries.

    Oh by the way, the guy that ordered an LED and two switches on your website the wednesday night was me :-)

    Thanks,

    David

  11. #11
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    2,231
    If the batteries are protected cells, it may be that the protection circuit is kicking at the large current draw that occurs with a direct driven P7
    Last edited by Vancbiker; 03-23-2012 at 11:54 AM. Reason: bad spelling

  12. #12
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    Quote Originally Posted by Vancbiker View Post
    If the batteries are protected cells, it may be that the protection circuit is kicking at the large current draw that occurs with a direct driven P7
    I was thinking that and leaning that way but its strange that it's two single batteries..

    All four batteries are trustfire and have protection circuits. 2 work with the LED and two dont.

  13. #13
    Carbon8er
    Reputation: El34's Avatar
    Join Date
    Jan 2009
    Posts
    1,130
    Hmmm, I don't know what is going on.

    I have not run into a problem like this myself.

    All the batteries I run are protected cells, but I have never had them shut down.

    But, all my builds except really early ones have the AMC7135 boards as current limiters.

    I run that triple P7 of mine full blast on 7 x 18650's in parallel with no driver at all and you would think that would be the worst case scenario, but it still thrives.
    That's roughly 2.5 amps x 3 = 7.5 amps being drawn from that battery pack direct drive.

    Give the new LED a whirl and see what happens.
    If it's the LED, maybe it would still be usefull in a flashlight?

  14. #14
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    2,231
    Quote Originally Posted by El34 View Post
    I run that triple P7 of mine full blast on 7 x 18650's in parallel with no driver at all and you would think that would be the worst case scenario, but it still thrives.
    That's roughly 2.5 amps x 3 = 7.5 amps being drawn from that battery pack direct drive.
    In that case each of the 7 cells only needs to supply a bit over one Amp. No problem at all.

  15. #15
    Carbon8er
    Reputation: El34's Avatar
    Join Date
    Jan 2009
    Posts
    1,130
    Yes but I also have direct drive P7 flashlights with proctected cells
    One battery provides all the current draw in that situation.

    Who knows, maybe his specfic batteries are the cause

    Have to see how how the P7 swap out goes

  16. #16
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    Out of curiosity, I decided to see what putting the questionable batteries in the holder would do versus direct to the led. I thought maybe with more resistance because of the length of the wire plus the connectors maybe it might stay lit. Surprisingly the led did stay lit. I measured the voltage at the led connectors and it was basically the same as when i checked it at the battery so I am a little confused as to why that worked.

    As another test I drained the questionable battery with my flash light to a voltage less than the other batteries that do work with the LED. Connected it directly to the LED and it still did not stay lit.

    It seems very strange but I'm thinking that when directly connected to the LED, it must over draw the battery causing its protection circuit to shut it off. Im no electrician but the batteries are 2400maH batteries and the LED can draw 2800maH. So would a 2800maH battery work better?

    David

  17. #17
    Carbon8er
    Reputation: El34's Avatar
    Join Date
    Jan 2009
    Posts
    1,130
    The LED can draw way more than 2800ma.
    The LED does not regulate itself.
    That's why the current limiter board is a good idea
    I have seen P7's draw 3.2 amps when direct driven

    I would just give up on the goofy battery if I were you and use it in a flashlight by itself

  18. #18
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    So I got the new LED today. Thanks for the fast shipping El34...

    I tried the two "faulty" batteries with the new LED and it did the same thing. I tried my other batteries and the LED stayed lit. Brand new LED, I'm saying faulty battery protection circuit. Or maybe the other way around!! :-)

    I think there is something to be said about solder here... When my light was flickering off and I thought it was the switch, then the LED, and now the batteries :-). I had all my connections soldered. Now as I am testing things, I dont have solders connections and the LED will actual stay lit with the bad batteries. If i connect the battery directly to the LED is doesn't stay lit and with my soldered connections it also would not. It must be that that little bit of resistance with only twisted wires is enough to keep the LED from over drawing the battery?


    David

  19. #19
    Carbon8er
    Reputation: El34's Avatar
    Join Date
    Jan 2009
    Posts
    1,130
    I solder all my packs but have not run into this situation before.
    Maybe the protection circuits got damaged during soldering?

    I use a 40+ watt iron and do each solder point very quickly to keep the heat as low as possible

    Hard to say what happened to those two batteries but at least you found the source

  20. #20
    mtbr member
    Reputation:
    Join Date
    Jul 2008
    Posts
    124
    Oh well, the new LED is in there and everything is all put back together. Can wait for a night ride...

    Thanks for all the posts, I was going a little crazy there...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •