• 12-12-2012
    troutie-mtb
    Series connecting different leds question
    As the title would there be any problems connecting in series say
    1 MTG2 (6 volt /3amps ) with 1 or 2 XMLs (3 volts / 3 amps )
  • 12-13-2012
    Toaster79
    No problems. In series voltages add. current remains the same over all of the LEDs. You can take single MT-G as 2 series XM-Ls.
  • 12-13-2012
    Toaster79
    Double post
  • 12-13-2012
    Toaster79
    Triple post
  • 12-13-2012
    troutie-mtb
    Cheers Toaster
    Cheers Toaster
    Cheers Toaster


    Betcha cant see where this is going
  • 12-13-2012
    Toaster79
    You're building another mother of all lights? Where else would it go, when you ask the question :D I'd say MT-G2 in 80mm reflector and 2 XM-Ls in a tad smaller reflectors?
  • 12-13-2012
    troutie-mtb
    Quote:

    Originally Posted by Toaster79 View Post
    You're building another mother of all lights? Where else would it go, when you ask the question :D I'd say MT-G2 in 80mm reflector and 2 XM-Ls in a tad smaller reflectors?

    Close
    thinking MTG2 and 2 XMLs in the same 80 mm reflector

    was thinking 2 MTG2s but at nearly 10 mm that wont work as need one to be dead centre

    and just been reading up the specs since IRV_USC suggested the MTG2 and at over 1500 lumens why are we not using them instead of XMLs
  • 12-13-2012
    Toaster79
    They are HUGE. Who wants 90-100mm diameter light head on a bicycle? G2 goes up to 1800 lumens in 5000K color temp. I've been considering building a light around this LED, but never really found a normal size reflector. 50mm would be about the biggest for my taste, but that would be quiet a floody one, so instead of single 80mm reflector I'd rather have two 40mm ones with XM-Ls. But that's just me.
    But, on the other hand, I might order a few pieces and some different reflectors and just see what works best. Still have some round 6061-T6 stock left to build some toys.

    An Idea crossed my mind a while ago, when I saw Cree CXA2011 on cutter's web site. It's 40W domeless emitter, but Vf is 40-48V so, the driver would be PITA to find (obviously boost). When dedoming LEDs in reflectors there's increase of throw, so a domeless reflector would throw further in that 80mm reflector.

    edit: Mixing color tints might give you some funky color shifting in the beam.
  • 12-13-2012
    bikerjay
    I saw something over on candle power forums about the mt-g2 being generally used very conservatively and under driven but being capable of over 2600 lumen. I think it with an 80mm reflector could make a great automotive/moto light especially in 4000k. The various voltage options are interesting.
  • 12-13-2012
    irv_usc
    Tee hee. glad to see someone with skills is looking into the mt-g2 as a candidate, even as experiment.

    From the specs it seems like a single mt-g2 would make a great light. There are even several different optics for it that would give you different shaped beams from a single emitter.

    by the way, what got me interested in that emitter is a post on candlepowerforums talking about 2500+ lumens out the chip. yes it's an array but you can still get a smooth beam.

    30mm carclo optics for mt-g2: Cree MT–G2 & Carclo Optics
  • 12-13-2012
    Vancbiker
    Quote:

    Originally Posted by irv_usc View Post
    30mm carclo optics for mt-g2: Cree MT–G2 & Carclo Optics

    With the tightest version at 22.5 degree FWHM it's too floody for a mt bike light IMO. Get that down to less than 10 degrees and you'll have something.
  • 12-13-2012
    mrradlos
    Quote:

    Originally Posted by Vancbiker View Post
    With the tightest version at 22.5 degree FWHM it's too floody for a mt bike light IMO. Get that down to less than 10 degrees and you'll have something.

    ... might be possible (p. 16)
  • 12-14-2012
    Vancbiker
    Quote:

    Originally Posted by mrradlos View Post
    ... might be possible (p. 16)

    Beautiful beam but it's back to an 80mm reflector. Larger than I want to build with