Blue LED's will not light.

Discussion in 'Electronics' started by Richard Dobson, May 22, 2013.

  1. Richard Dobson

    Richard Dobson New Member

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    Having trouble getting blue LED's on booms 4 and 6 to light. Red LED's on boom one light. Lights are from Quadrocopter.
    I have two sets of 3 red LED's on boom one split to one jst going to three way splitter in the hub.
    One set of 3 blue on booms 4 and 6 going to the three way splitter in hub.
    The three in one out splitter in the hub is connected to PCB board on S1.
    PCB board is connected to the FCB via servo cable to top side of servo1 brown wire to inside on FCB and brown to J7, red to 5v, and yellow to J6 on the PCB board.
    Power is from +/- pads on bottom of FCB.
    Trouble shooting.
    Tested three to one splitter in hub. Red lights will light on any of the three in's.
    Tested lights work. Plugged 2 cell 7.4 volt direct to lights. Reds light blue will not. Plugged 3 cell 11.1v to blue lights and they work.
    Tested for shorts on PCB board found none. LED's on PCB board light up.
    Kopter Tool setting are set for low voltage flashing and red led's flash blue never light up.
    Anyone have ideas?
    Picture attached. IMG_6693.jpg
     
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hi Richard:

    I think you've discovered with your testing that the LEDs are designed to work at 12volts -- the technology of the Red LEDS must allow them to work at less voltage than the blues. Double check with QC, but I think you should be feeding 12v to both Red and Blue LEDS.

    Andy.
     
  3. Gary Haynes

    Gary Haynes Administrator
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    Richard do you want all of the lights to flash? If the Blue's are simply going to be on all the time I would pull power from the main battery and not through the extension board.
     
  4. Richard Dobson

    Richard Dobson New Member

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    Thank you for your responses,
    I would like all lights to flash, and according to the instructions they should through the PCB board. I am waiting for a response from Quadrocopter now. I will let you know what we discover.
     
  5. Richard Dobson

    Richard Dobson New Member

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    As expected my error. I thought I checked everything but did not check JST connectors for possibility of being reversed. Guess what. Blue LED's JST's are reversed. Thanks Quadrocopter for asking the question.
     

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