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  1. #1
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    New Light (in over my head)

    Hey guys this is the new design for my light, due to lack of funds instead of getting a custom body made im going to sacrafise my Maglite 4D and use the head to accomidate both driver and emitters.

    Its going to accomidate 2 XML's and a triple XPG the two XML's will run in series with the triple XPG which I have wired up in parallel. So will run XML- 3xXPG (parallel)- XML. All powered with a B6FLEX driver set up at 2800 max amps running of a 14.8v 4s2p 18650 battery pack.

    My question is firstly is this a good idea to set up like this? and secondly will the Maglite head be able to cope with the heat created? I was hoping to put some finage in the body the increase surface area and have a 48mm diameter by 8mm pill to place all the leds onto.

    Adleysh
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  2. #2
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    P.S I dont know why it decided to cut the top off the drawings

  3. #3
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    what's the triple XP-G for? The 2 XM-Ls should give you more than enough flood and most people think that the 20mm triple optics with XP-G are pretty floody. If you're set on that design I'd recommend a triple XP-E2 instead, you'll get far more throw out of it.

    For the amount of effort this is going to take, I'd personally recommend one of the Easy2LED 35mm housings and a triple XM-L. Tons of light, super easy build and plenty of cooling. They're pretty reasonably priced for what you get too.

  4. #4
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    I kind of doubt you'll have enough surface area, but ... If this is an Inventor file (looks like an .IDW) ... Add another sketch to the part, fill the inside via another extrusion, then look at the properties of the file, by right-clicking on the part in the browser panel, go to the physical tab of the dialogue box, and look at the area ... This will be the external surface area of the housing.

    Also,
    Set the material type to see an accurate weight ... Under document setting (tools tab), change the units, if needed ... I prefer to view such things in grams YMMV.

  5. #5
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    Quote Originally Posted by mattthemuppet View Post
    what's the triple XP-G for? The 2 XM-Ls should give you more than enough flood and most people think that the 20mm triple optics with XP-G are pretty floody. If you're set on that design I'd recommend a triple XP-E2 instead, you'll get far more throw out of it.

    For the amount of effort this is going to take, I'd personally recommend one of the Easy2LED 35mm housings and a triple XM-L. Tons of light, super easy build and plenty of cooling. They're pretty reasonably priced for what you get too.

    Come on Matt effort and struggling is part and parcel of this diy lark not doing it the easy way .
    Mag heads make great doner hosts go for it Adleysh

    but do agree about the triple xp`s being a bit pointless I would go for 3 XMLs and the 50 mm Rocket optic Cutter Electronics
    works well with the XMls

  6. #6
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    just saying

  7. #7
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    Thanks for the replys guy's and Happy New Year to all.

    There is a little bit of method in my madness, I was looking to use this light not just for riding but also to use for working on the car, camping etc.... so was looking for something really floody but that could also be used on the bike. I know that generalising a light isnt the best of ideas but am stuck for money atm and cant afford to get any more parts in

    Originally it was just going to be a double XML but I had the triple XPG left over from converting a mini Maglite tourch so thought i would throw it in anyways. So my question now is do i go back to the original plan of just double XML or do I go ahead with the additional XPG's? Will it be usable as a bike light with the limited throw?

    Also the reason for not getting one of the easy2diy bodys is I have already made a helmet light using one of the smaller body's and thought I would try a different path for the next build.

    Cheers,

    adleysh

  8. #8
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    I'd stick to the 2x XM-L + 3xXP-G idea. Additional amount of light is always welcome. For the triple I would use Carclo 10507 (assuming it is the 20mm PCB) optics and for the XM-Ls I would use something like LXP-RS, LXM, LC1, or similar to get the tightest possible beam shape. The triple XP-G might get washed out by the XM-Ls so I would even consider double driver setup to be able to use XP-Gs separately, using two buck drivers and 4S battery setup.

    Just my 2 cents

  9. #9
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    Quote Originally Posted by Toaster79 View Post
    I'd stick to the 2x XM-L + 3xXP-G idea. Additional amount of light is always welcome. For the triple I would use Carclo 10507 (assuming it is the 20mm PCB) optics and for the XM-Ls I would use something like LXP-RS, LXM, LC1, or similar to get the tightest possible beam shape. The triple XP-G might get washed out by the XM-Ls so I would even consider double driver setup to be able to use XP-Gs separately, using two buck drivers and 4S battery setup.

    Just my 2 cents
    Ok will stick in the additional XPG's the triple lens I have for them is the lens you suggested and for the XML's I went for the Carclo 20mm plain tight lens 12.4 degrees, Do you think that would be ok?

    How would I wire up the two drivers if i went down that route? The led side would be fine but on the battery side would i wire the drivers up in series or parallel or possibly run each driver of a different battery. Say if i take my 4s2p and split it to make 2x 4s1p?

    cheers

  10. #10
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    If you decide for the two drivers setup, you would be wiring one driver with 2 XM-Ls in series and one driver with 3 XP-Gs in series. If using say B3Flex you would wire 4S2P battery and connect it to both drivers-prallel. No need to split the battery unless you want to loose some weight.

    Cant help you with the 20mm Carclo since I haven't used it my self nor have I seen any beam shots, but I guess 12.4 deg. should do fine if that's 12.4 for the XM-L and not for any smaller emitter.

    Good luck with the build!

  11. #11
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    I think matt tried the carclo 20mm optic and said that the Ledil LC1 was much better..
    If you have an RS local you can get the LC1 from there... They are only a couple of quid.

    personally I would just use 3 XM-L's, and drop the XP-G's.
    I would have thought the 3 XP-G's would put out more heat than 1 XM-L?

  12. #12
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    I'd personally go with the 10deg XM-L optics from LED-DNA over any others - the LC1 is fine, but too spotty IMO, and I wasn't all that impressed with the Carclo. It's alright and if it was the only one available it would do, but there are plenty better optics out there. If I wasn't building a new helmet light, I would have swapped out the Carclo for a LED DNA optic ages ago.

  13. #13
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    Quote Originally Posted by Goldigger View Post
    personally I would just use 3 XM-L's, and drop the XP-G's.
    I would have thought the 3 XP-G's would put out more heat than 1 XM-L?
    Another vote for dropping the triple xpg for an XML, I thinks its time to get some ordered, cheers guys as I am new to this your experiences will no doubt save me time and effort

  14. #14
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    Quote Originally Posted by bikeabuser View Post
    I kind of doubt you'll have enough surface area, but ... If this is an Inventor file (looks like an .IDW) ... Add another sketch to the part, fill the inside via another extrusion, then look at the properties of the file, by right-clicking on the part in the browser panel, go to the physical tab of the dialogue box, and look at the area ... This will be the external surface area of the housing.

    Also,
    Set the material type to see an accurate weight ... Under document setting (tools tab), change the units, if needed ... I prefer to view such things in grams YMMV.
    Finally got round to doing this little trick and the total surface area added up to near enough 1300mm≤.
    If any one has the calculation for working out the surface area needed for such a light that would be great or even a link to a thread already set up as i cant seem to find one.

    cheers.

  15. #15
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    That cant be right its only just over 2 sq inches by that reckoning .

    Anyways screw the hi tech approach and go with your finning of the mag head and whack in 3 xmls I have done a few mag heads and they cope fine with the heat in this damp cold country .

  16. #16
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    as far as google tells me 1in.sq = 645mm.sq and the general rule of thumb used on here is 1W per in.sq surface area minimum (ie. with some airflow). A more conservative rule is 1W per 2in.sq.

    So, 1300mm.sq I think = 2in.sq, which just doesn't sound right for a Maglite head. I would have thought you'd be in the 15in.sq range at least, as the circumference of the head should be around 8in (phi r squared right? and it's 50mm diameter).

    1 XM-L @3A is around 10W, give or take, so it's relatively easy to work out from there.

  17. #17
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    Quote Originally Posted by troutie-mtb View Post
    That cant be right its only just over 2 sq inches by that reckoning .

    Anyways screw the hi tech approach and go with your finning of the mag head and whack in 3 xmls I have done a few mag heads and they cope fine with the heat in this damp cold country .
    Sorry guys forgot a zero good job i dont work for nasa, its 13000mm≤ which should give me 20inch≤ so looks like I will be a bit short of surface area.

    As troutie says in our loverly climate I may get away with it, but will need to set the H6Flex at around 60 degrees for protection.

  18. #18
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    Quote Originally Posted by mattthemuppet View Post
    as far as google tells me 1in.sq = 645mm.sq and the general rule of thumb used on here is 1W per in.sq surface area minimum (ie. with some airflow). A more conservative rule is 1W per 2in.sq.

    So, 1300mm.sq I think = 2in.sq, which just doesn't sound right for a Maglite head. I would have thought you'd be in the 15in.sq range at least, as the circumference of the head should be around 8in (phi r squared right? and it's 50mm diameter).

    1 XM-L @3A is around 10W, give or take, so it's relatively easy to work out from there.
    So you're saying that my 6 XPG2 @ 1.5A in about 16.5" of surface area isn't going to live very long. LOL - I knew that I was overtaxing the housing, but I didn't realize by how much.

  19. #19
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    Quote Originally Posted by adrenalnjunky View Post
    So you're saying that my 6 XPG2 @ 1.5A in about 16.5" of surface area isn't going to live very long. LOL - I knew that I was overtaxing the housing, but I didn't realize by how much.
    if the driver doesn't have any temp protection and you stand around with it on full for long, then yes, it probably won't last long Otherwise you'll probably be fine with some airflow and low air temps. The only time I run into heat problems with my lights is in the middle of summer, with air temps between -10 and -20C, I don't usually have too many problems!

  20. #20
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    Quote Originally Posted by mattthemuppet View Post
    if the driver doesn't have any temp protection and you stand around with it on full for long, then yes, it probably won't last long Otherwise you'll probably be fine with some airflow and low air temps. The only time I run into heat problems with my lights is in the middle of summer, with air temps between -10 and -20C, I don't usually have too many problems!
    Hbflex is setup for temp cutoff - but I also have my low power setting at about 750mah, which does get the wattage numbers better than 1"/watt.

  21. #21
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    Quote Originally Posted by adrenalnjunky View Post
    Hbflex is setup for temp cutoff - but I also have my low power setting at about 750mah, which does get the wattage numbers better than 1"/watt.
    With the H6Flex max set to 2800mah does any one know what will be the levels:

    L1?
    L2?
    L3?
    L4?
    L5 2800mah

    cheers

  22. #22
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    I believe that George (from TaskLED) has stated that each level decreases ~50% from the previous level, that each level is not a preset value.

    edit: found his post: Flex power levels

    So L5 = 2800
    L4 = 1400
    L3 = 700
    L2 = 350
    L1 = the lowest the driver can stably provide ~50ma

  23. #23
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    Well nevermind - George provides tables for the H6flex in the technical papers:

    H6Flex Driver Technical Information
    Attached Thumbnails Attached Thumbnails New Light (in over my head)-tableh6flex.jpg  


  24. #24
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    Quote Originally Posted by adrenalnjunky View Post
    I believe that George (from TaskLED) has stated that each level decreases ~50% from the previous level, that each level is not a preset value.

    edit: found his post: Flex power levels

    So L5 = 2800
    L4 = 1400
    L3 = 700
    L2 = 350
    L1 = the lowest the driver can stably provide ~50ma
    Perfect thank you . With the housing not having quite enough surface area (2/3's) I'm going to have to choose carfully in order to have enough light for constant use, max for quick downhills and a good low level for cooling it all down on the fire roads.

  25. #25
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    then I'd use L2 or 3 for fire roads, and 4 & 5 as your low and high. Put the driver in threemode or trimode.

    Trimode allows each click to cycle through all 3 levels. In threemode the momentary click toggles between the 2 brightest levels, while a long press puts it into the low mode.

    I like Threemode, cause in the woods I might cycle thru the high and medium levels based on the immediate trail ahead, but I leave low at the 50ma level for when I'm stopped or needing to work on my bike, etc. So I don't need to toggle to that level while I'm riding.

  26. #26
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    Also while skimming you tube ( as you do ) found this little gem. It's a new silicone putty which could be used on things like cable strain or little leaks. Never seen one this user friendly before so might get a batch and do some tests as it will stick metal platic aNd glass. It is very thermally insulating tho so don't put it on parts that need heat transfer

    https://www.youtube.com/watch?v=8fOS...e_gdata_player

  27. #27
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    I've used it before and it's flexibility is too low for strain relief, although it sticks to aluminium and plastic just fine. I used it as a strain relief on a couple of commuter lights and on both of them it split after some time in my pannier. Still working fine on my bar light (strain relief for the remote) where it doesn't get subjected to any strain, ironically enough.

  28. #28
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    Quote Originally Posted by mattthemuppet View Post
    I've used it before and it's flexibility is too low for strain relief, although it sticks to aluminium and plastic just fine. I used it as a strain relief on a couple of commuter lights and on both of them it split after some time in my pannier. Still working fine on my bar light (strain relief for the remote) where it doesn't get subjected to any strain, ironically enough.
    Cheers for the tip will not be using this for a strain relief, possibly keep it for surfboard repairs when travelling.

  29. #29
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    I don't have any experience with other many other optics, but I'm using one Carclo tight and one narrow in my 2 xml setup, and I'm very happy with the beam. That 12 degree figure you were looking at is using an xpg, it's 17 degrees with an xml, which I like for a bar light. Plus they are cheap and readily available. Looked at trying some Ledils when I was doing my build, but the ones I were interested in were nearly impossible to come by.

    Good luck on your build!

  30. #30
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    Quote Originally Posted by Clipless in PA View Post
    I don't have any experience with other many other optics, but I'm using one Carclo tight and one narrow in my 2 xml setup, and I'm very happy with the beam. That 12 degree figure you were looking at is using an xpg, it's 17 degrees with an xml, which I like for a bar light. Plus they are cheap and readily available. Looked at trying some Ledils when I was doing my build, but the ones I were interested in were nearly impossible to come by.

    Good luck on your build!
    I Have got a Ledil FA11937 in my single xml helmet light and it works very well, So last night I swapped out the ledil for the carclo just to see what the difference is, It wasn't huge but the ledil did produce a cleaner almost more efficient light. Which made me want to use the Ledil, however I noticed that the stack height was taller on the ledil which would mean having a thinner pill thickness the fit everything in the head. So seeing as there was no huge difference with performance I will probably use the caclo to try and keep a better heat path.

  31. #31
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    Quote Originally Posted by adleysh View Post
    So last night I swapped out the ledil for the carclo just to see what the difference is, It wasn't huge but the ledil did produce a cleaner almost more efficient light. Which made me want to use the Ledil,
    Of the Carclo optics I have used on MCEs and XPGs, I have never found them to make a very good beam. Floodlights, even with their tightest spec.

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    I wonder what the difference is - I'm running carclo 20mm 12.4* plain tight/narrows on a dual XP-G2 light and feel like it has a really nice hotspot.

    Sometimes I only run a helmet light though, and do like the spill/fill I get out of this setup, not floody, but nice peripheral light.

  33. #33
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    Quote Originally Posted by adrenalnjunky View Post
    I wonder what the difference is - I'm running carclo 20mm 12.4* plain tight/narrows on a dual XP-G2 light and feel like it has a really nice hotspot.
    I have not used the Carclo 20mm series on XPGs, just their 10mm series. The 20s I used were on MCEs. The 10mm on XPG suits many, I just find it too short on throw and too wide. The 20mm on an MCE was just horrible. Very wide and dispersed beam even with the tightest available at the time

  34. #34
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    Got everything all rigged up for a test and have come across a problem. When I put the light on full 2800mah after around 2-3 minutes it flashes 9-10 times slowly and then turns off. I have the B6flex driver driving it. Is this a low voltage cut off?

    At the moment its rigged up with the original plan as I am wating for an XML and triple optic so its the two XML's in series with a triple XPG (parallel).

    Due to the charger that I bought having a fault it had to be returned so the batteries are not fully charged, they are at the same charge state as when delivered.

    cheers.

  35. #35
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    Sounds like low voltage cut off for the flex driver. I've only hit that once so don't remember exactly the flash pattern, but it sounds right. Get a voltmeter in there and look at the battery voltage under load.

  36. #36
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    That's the voltage cut. You know you can modify that threshold and if it cuts the power or not. TaskLED drivers are incredibly customizable. I usually have to draw out a flowchart of what programming (and in what order) needs to be done on any of mine.

    My 1st step is always to put it in threemode (that's what I like to run) - you have to select that before any of the other programming, if not you have to start over again.

  37. #37
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    Quote Originally Posted by adrenalnjunky View Post
    That's the voltage cut. You know you can modify that threshold and if it cuts the power or not. TaskLED drivers are incredibly customizable. I usually have to draw out a flowchart of what programming (and in what order) needs to be done on any of mine.

    My 1st step is always to put it in threemode (that's what I like to run) - you have to select that before any of the other programming, if not you have to start over again.
    So far I have set it up to 2800mah, trimode, 60 degree=power reduce

    What voltage do you program for low with a 4s2p pack?
    Will need to change it from turning off as that could be dangerous.
    The cells I am using are protected already does that mean I can set the v low warning lower?

  38. #38
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    Quote Originally Posted by adleysh View Post
    So far I have set it up to 2800mah, trimode, 60 degree=power reduce

    What voltage do you program for low with a 4s2p pack?
    Will need to change it from turning off as that could be dangerous.
    The cells I am using are protected already does that mean I can set the v low warning lower?
    Everyone has a preference for how low they like to discharge their cells - 2.75v - 2.8v per series cell would likely be appropriate for a 4s pack (the parallel cells don't contribute, as a parallel pairing should discharge as a balanced pair. So your cutoff setting or low warn setting should be 11v or 11.2 or in that ballpark. Remember, under load your pack will sag lower than the volt meter says when not under load.

    You can also set up a mid-point warning on that driver - where you jsut get a blink to notify you you've hit a mid-charge voltage. ~3.0 - 3.2v per cell is not a bad point to set that warning at if you want it - so 12-12.8v.

    I usually set mine to not turn off, but keep repeating the low voltage warning flashes every 30 secs or so. I'd rather fry a battery than ride into a tree due to a power cutout. But that's just me.

  39. #39
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    Result

    Ok everyone, as you have helped so much over the last few weeks I thought it would only be fare to let you have a look at the almost finished light

    The bits that are changing are as follows:

    - Swapping out the triple XPG for another XML
    - Changing the optics to the triple XML optic
    - Possibly boosting up from 2800mah to 3000mah?
    Attached Images Attached Images    

  40. #40
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    Looks nice!

    since your amperage setting is just a setting in your driver, and not requiring a different driver be wired up, why not. although a lot of folks feel that last couple of lumens you get out of bumping over 2.8A, is not really worth the tradeoff you pick up in heat.

    then again - I'm betting you're not planning on running on high all the time.

  41. #41
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    Quote Originally Posted by adrenalnjunky View Post
    Looks nice!

    since your amperage setting is just a setting in your driver, and not requiring a different driver be wired up, why not. although a lot of folks feel that last couple of lumens you get out of bumping over 2.8A, is not really worth the tradeoff you pick up in heat.

    then again - I'm betting you're not planning on running on high all the time.
    Yeah am fighting the battle over heat and light, but L4 gets increased if I was to go for 3A so more likely to run it on medium rather than high. Were at 2.8A i'm more tempted to run on high most of the time, unless on fire roads.

    Will post some beam shots asap.

  42. #42
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    Having a little problem with this light

    It seems that the 4s2p battery pack that I made for this light will not power it sufficiently. It will turn onto max 2800mah, but after around 5-10 minutes the voltage has dipped to below minimum threshold set at 11v and turns the light off. On medium it seems to power the light fine.

    I can only think of three reasons for this problem:
    - The battery pack I made has a dodgy cell which is causing the drop in voltage?
    - The light as it is set up, XML - triple xpg (parrallel) - XML is drawing off to much power?
    - The batteries are S#*% and will not support the light on high. The battery's are ultrafire 18650's 3000mah and I know they can be dodgy which is the reason I used 8 battery's not 4.

    Any help would be much appreciated

  43. #43
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    Assuming your pack is built properly, your first idea seems the most likely cause. Your LED setup is ~10Vf at 2.8A. This makes ~28W. If your pack is all good and assuming the 3000mA labeled cells are closer to 2000mA the pack will have ~56Wh of capacity. This should not sag to the shut off voltage.

    A14.4V pack is best wired as a 2P4S configuration. Many do a 4S2P configuration. There is a difference. The voltage with either is 14.4 nominal, but a duff cell in a 4S2P pack effectively turns it into a 4S1P.

  44. #44
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    Quote Originally Posted by Vancbiker View Post
    Assuming your pack is built properly, your first idea seems the most likely cause. Your LED setup is ~10Vf at 2.8A. This makes ~28W. If your pack is all good and assuming the 3000mA labeled cells are closer to 2000mA the pack will have ~56Wh of capacity. This should not sag to the shut off voltage.

    A14.4V pack is best wired as a 2P4S configuration. Many do a 4S2P configuration. There is a difference. The voltage with either is 14.4 nominal, but a duff cell in a 4S2P pack effectively turns it into a 4S1P.
    I belive I have made my battery pack 4s2p, how would I wire it the other way around?
    I have balance wires in and they seem so be correct as when i put a volt metre to the balance block it reads 3.7,7.4,11.1,14.8 in sequence.

    Any way I took all the batteries out of the case and measured them indervidually and they all read the same voltage of around 3.5v as this is after running the light a while. Would I find a cell with a significant difference if it was bad?

  45. #45
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    Here is a pic of the the pack I made and the balance read out on the charger.

    The pack is basically two 4s1p packs that I have combined to make 4s2p but I linked after each cell to bridge pairs of batteries to connect a balance wire.

    so I have:
    1 pair = 3.7v
    2 pair = 7.4v
    3 pair = 11.1v
    4 pair = 14.8v

    Is this correct or have I messed things up here?
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    See post 17 in this thread for best series-parallel wiring.

    Building a four cell battery pack. How to charge it?

    In my experience in using some cells salvaged from laptop packs, I could only find the bad cells when voltage testing under a load.
    Last edited by Vancbiker; 02-03-2013 at 12:58 PM. Reason: Added information

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    Quote Originally Posted by adleysh View Post

    Any way I took all the batteries out of the case and measured them indervidually and they all read the same voltage of around 3.5v as this is after running the light a while. Would I find a cell with a significant difference if it was bad?
    Not unless you are testing the cells under load ... A cell can show proper voltage, and drop drastically when a load is applied.

    Ever seen a load test on a car battery ?
    Same idea ... It can read good on a basic voltage check, but under load might show one or more cells have failed.

  48. #48
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    Quote Originally Posted by bikeabuser View Post
    Not unless you are testing the cells under load ... A cell can show proper voltage, and drop drastically when a load is applied.

    Ever seen a load test on a car battery ?
    Same idea ... It can read good on a basic voltage check, but under load might show one or more cells have failed.
    Checked the amps being drawn under load and when first turned on I was only getting 0.91A which quickly (within 5 minutes) dropped to 0.15A

    Looks like the cheap cells came back to bite me. Am now considering buying a turnigy 14.8v 5000mah 4s1p lipo battery and giving up with li ion all together. Any one with experience with using lipo instead of li ion, I cant seem to find a reason why searching forums they aren't used on bike lights more often?

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    I used lipo packs for years with no problems. Just make sure you are using a driver that has voltage warning on it so you don't discharge the packs too far. If you do not have a driver like this just buy a cheap RC Lipo warning buzzer that connects to the balance leads, it will tell you when the battery is nearing the lower voltage level with a nice 90+dB buzzer, which will also scare the crap out of you if riding a quiet and spooky trail.

    As for normal lipo charging precautions, I make sure I charge the packs out of the house (fire risk) and not mounting them in such a way that they can be punctured (highly unlikely though).
    Last edited by brad72; 02-03-2013 at 09:29 PM.

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    that's a scarily unbalanced pack! Don't let crap Chinese cells put you off li-ions, just get some decent Sanyo 2600 cells from a reputable seller. They're not very expensive and work well. You can also go li-po, but li-ion tends to be more robust, have better energy density and more charge/ discharge cycles (at the expense of the humungous burst current ratings li-pos have which we don't really need).

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