Customs: Need help with LEDs...

Discussion in 'Creative General Discussion' started by yongkykun, Jul 19, 2009.

  1. yongkykun

    yongkykun Well-Known Member

    Joined:
    Jun 22, 2009
    Posts:
    478
    Trophy Points:
    76
    Likes:
    +0
    Hi Radicons,

    I completely forgot everything I knew about electricity back at school. Please do help me with this.

    I'd like to install 3 LEDs with this specifications:
    Forward Voltage : 3.2 - 3.6
    Forward Current : 20mA
    Lens Colour : Water Clear
    Emitting Colour : Blue
    Size : 3mm

    And another 2 with the same specs but different size:
    Forward Voltage : 3.2 - 3.6
    Forward Current : 20mA
    Lens Colour : Water Clear
    Emitting Colour : White
    Size : 5mm

    Those two LED groups will need to have two different power sources. My questions are:
    1. How do I go and arrange the components? I mean, do I connect those LEDs one leg attached to the others in a serial arrangement or do I have to go with parallel arrangement?
    2. Do I need resistors? Or any other electrical components? If I do, could you please tell me what I need to put on my shopping list?
    3. Due to the lack of space in my future custom figure, I need to know if I need to use AAA or AA or coin batteries? How many of those batteries do I need for each group (2 LEDs and 3 LEDs)?
    4. If I install more than the necessary number of batteries, will that make the LEDs glow brighter? And what are the consequences?

    If you could give me a simple plan on how to arrange the components, I'll be more than indebted to you. Thank you in advance. Looking forward to learning more from you guys.

    -Yongky
     
  2. encline

    encline customizer of love TFW2005 Supporter

    Joined:
    Oct 5, 2006
    Posts:
    5,620
    News Credits:
    11
    Trophy Points:
    261
    Likes:
    +11
    You lost me at all those numbers!!!! I just hook stuff up in circles and use hight voltage batteries:) 

    Seriously, I am sure big hank will stop by to help you out!!!!
     
  3. David Hingtgen

    David Hingtgen Chromaticon

    Joined:
    Jul 1, 2002
    Posts:
    8,297
    News Credits:
    2
    Trophy Points:
    247
    Likes:
    +90
    In short, all your questions are inter-related. The answer to all of them is "if you do it that way". Resistors? Depends on the battery source--some LED and battery combos will be "just right" as-is. Serial vs parallel---how you wire them will affect voltage/resistance from the battery source. What batteries should you use? Depends on how you wired them...

    Basically---you need to either pick a wiring arrangement or a battery source, then that will determine the other aspects.

    Or, just calculate out what's needed for every option, and then do whichever seems easiest/cheapest.
     
  4. big hank

    big hank Resident Slacker-Basher

    Joined:
    Nov 23, 2007
    Posts:
    4,008
    News Credits:
    10
    Trophy Points:
    151
    Likes:
    +10
    Why do you need 2 power supplies? The specs show they all can play nicely together off one power source, unless it's a real estate issue. The LED diameter has no impact on the circuit, the only spec you didn't provide that may cause issue is the brightness emmitted, rated in MCD. Do you have a spec available for this?


    I prefer parallel in TFs due to the fact that you can get away with smaller battery packs, if you ran all 5 LEDs in serial you would need 16 volts worth of power. Two size A/M-27 batteries would yield 24 volts (plenty of power) with a safe current load at a size of about a single AAAA battery. In parallel all ya need is just one A/M27 for lots of power. The trade off for parallel is you will have more wiring to run, but it's a negligible difference. Or if you have to run two battery packs, you could get even smaller batteries, in parallel milliamps of current is the key. You need enough to juice all the LEDs.

    I pretty much never run resistors in TFs. It's a component you can live without (unless you plan on lighting the LEDs with a car battery, LOL). Finding the space for it can be more aggravating than changing out the battery twice a year instead of only once! If you feel you want resistors, figure out your battery set up and I'll calculate the resistor for you.

    Check the above answer again! Plus if you don't want to divulge the figure you are using give me a size class, I've got 4 button cells in a couple Deluxes, 2 button cells in a Scout. and I've shoe-horned an A/M-27 in a deluxe as well. Anything is possible.


    It will glow brighter, but not directly because of the number of batteries, or the increased voltage. It's all about the amperage, LEDs can handle voltages much higher than what they are rated, but higher mA ratings will increase brightness, and also blow the LEDs if pushed too high.

    That's gonna require a lot more info than you've given. Other than drawing a basic circuit and letting you plot out the components on your unnammed figure, there's not a lot of concrete info to give out!

    EDIT*** Here's a great link with a lot of good electronics discussion, as well as some great resource links!!

    http://www.tfw2005.com/boards/radicons-general-discussion/249563-here-where-i-get-great-leds.html
     
    Last edited: Jul 19, 2009
  5. yongkykun

    yongkykun Well-Known Member

    Joined:
    Jun 22, 2009
    Posts:
    478
    Trophy Points:
    76
    Likes:
    +0
    WOW that's one solid help there Big Hank! Thanks!

    It is real estate issue. Oh yeah I forgot to mention it, its 10,000 MCD.

    Is A/M27 the same as A23 (12volts battery)? Can you elaborate on the basic rule of thumb for a parallel wire job?

    Good to hear! I was kinda afraid that additional components like resistors and the like are compulsory for LEDs. I'll try and upload a rough schematics of my anonymous figure's LED and battery placements later tonight.

    Size class? I don't really know, maybe Leader. It's approx. 30-33cm tall. Still undecided about his height but its about that tall.

    So you're saying that the bigger the Ampere is the brighter it's going to be regardless of its Voltage?

    I'll try and make that schematics. I'm still afraid that this figure may not be able to stand what with it's legs being ball-jointed and his pelvic area being so narrow and all. You'll see what I mean once I got the schematics done. Thanks a lot Big Hank. And Encline, how did you know that Big Hank is going to help me out??? You're psychic?

    Thanks for the link but I always get mine from this UK site:
    Led-Depot - Top quality LED's at unbelievable prices.
    Lots of stuff and pretty cheap. Plus they carry those cool flexible LED strips.
     
  6. big hank

    big hank Resident Slacker-Basher

    Joined:
    Nov 23, 2007
    Posts:
    4,008
    News Credits:
    10
    Trophy Points:
    151
    Likes:
    +10
    Not a problem!:thumbs2: 



    10,000 is hella bright! I like to point out to folks my thoughts on brighter is better syndrome. I like to take scale into account, scale encompasses all aspects of the figure/model. If you were to install the 10,000MCD white lights into a Deluxe Skids' headlights, it would look as though he had those "store grand opening" searchlights for headlights. Just doesn't scale out for me. Check the attached image of my Skids, those headlights are around 160-200 MCD and look great. I'm not saying don't use 'em, just something to consider. Plus it will affect your battery consumption.



    Yep, same specs I believe, just a smaller diameter, check the pic!

    Basically you can get away with minimum voltage requirements with parallel. If you ran your three blue LEDs in series you would need at least 9.6 volts to light them, in parallel you only need 3.2 to light them all, albeit 3.2 is a tad too much to get away with just one button cell.

    As we know, you need to attach each leg of the 3 LEDs to the battery to make a parallel circuit, but the LEDs don't know if they are touching the battery or just a wire(which works as an extension of the battery). If you take a look at my super professional wiring diagram :dunce  there you can see they are both treated as parallel circuits. The circuit on the left will allow you to locate the battery and switch as far away as you need to accomodate transformation clearance, real estate, etc. In effect they are the same.



    Yeah, you can ditch the resistors for basic circuits, it's extraneous in my opinion.

    I'd like to see what you have in mind, I may be able to help out more that way.



    You definitely will be able to power 5 LEDs in that big if a bot!



    In effect, yes. I attached a pic of three blue LEDs, all the same spec (3mm, 2.6 minimum forward voltage, 20ma current, 160 MCD at those ratings). From left to right we have a 3 volt battery with modest amperage, middle is a 3v battery with higher amperage, and the one on the right is powered by 9 volts and major amperage! So the same exact LED displays different brightnesses at different amperages. This brings me back to scale, the one on the right is too bright to be, say, eyes for an Autobot. But may work well for a laser cannon or thruster. For the record, Skids is powered by amperage somewhere in between the leftmost LED and the middle.

    Also I added a pic showing various batteries, all of which represent a 3 volt power source with varying mA current ratings.



    He knows we Radicons are just good like that! Always ready to help out. But yes, he IS psychic!:sly2: 
     

    Attached Files:

  7. yongkykun

    yongkykun Well-Known Member

    Joined:
    Jun 22, 2009
    Posts:
    478
    Trophy Points:
    76
    Likes:
    +0
    woa, I didn't know that 10,000 MCD would be that bright :p  Now that I've learned much from you, sir, I know that melting my figure with LEDs ain't cool.

    [​IMG]

    This is the schematic for my project. I think I'm going to use a single 3v battery for each group of LEDs. I decided to use only 1 for the eyes. Dim is better for the eyes, I guess. I still don't know where to put the switches but, thanks to your diagram, at least now I know how to work the wires.

    So, Big Hank, please give some advice whether that schematic would work or not, and please give a few more pointers. And btw, I know so much more than when I first started this thread just from reading your very thorough guidance. Many thanks!
     

    Attached Files:

  8. big hank

    big hank Resident Slacker-Basher

    Joined:
    Nov 23, 2007
    Posts:
    4,008
    News Credits:
    10
    Trophy Points:
    151
    Likes:
    +10
    First off, excellent diagram! I wish I could do that stuff. I am just a pencil and paper type fossil!:D 

    Looks like you are down to 4 LEDs from 5. With each battery you can have a switch for each, so it looks like you want to turn on the white LEDs separate from the blues. Good job. Also if you are using a single cell per circuit, make sure your LEDs are rated 3v or less minimum forward voltage.

    So you are looking at 2 circuits actually, which is cool. I tend to use 2 circuits in my deluxes and bigger (one for the tail lights, one for the eyes and head lights)

    The circuits look good, and if the placement works for your figure, them your good to go! The swiches can go on either the + or - side, in between the battery and the wire leading to the LEDs. And that can be any where along the way you'll just need more or less wire as needed. The switch is just for opening the circuit, preventing current to flow. So put it wherever you wish, but keep in mind access for actually turning it on.

    On Skids, the switches are just inside the front and rear bumpers, so can activate them in either mode.

    BTW, one LED in the eyes will be plenty bright, but you could double up the battery for the eye/chest circuit, looks like a 2025. LEDs can take 2-3 of those without a problem and it will get you some more brightness if you choose.


    You can hit me up anytime, if I can help I'd be glad to.:thumb 
     
  9. yongkykun

    yongkykun Well-Known Member

    Joined:
    Jun 22, 2009
    Posts:
    478
    Trophy Points:
    76
    Likes:
    +0
    You have helped me big time man! Thanks so much. I'll get on it!
     

Share This Page