LED Wiring Questions

[food2000]

Hi Everyone,



I bought the axial simple controller which features 4 white leds and 2 red leds that all plug into a controller.



I was adding more length of wire for the white leds (i add a wire before which worked fine for 2 months then i wanted to add more so (used servo wire)) to fit my light pods and then... for some reason 2 / 4 leds wouldn't light up and i believe... burnt out as i can't get them to turn on.



I've ordered some new led bulbs to wire in but i have a few questions.



1) any idea why they burnt out? i know leds have a direction flow.. maybe reverse polarity burnt them?


2) I read http://www.rccrawler.com/forum/electronics/422460-how-wire-leds.html post about resistors... do i need to wire these resister along with the controller from axial?

{ controller } --------LED,+ resistor ----- LED + Resistor ---- etc..

Sorry, i am really new to led wiring and it's all kind of confusing.

 

[HumboldtEF]

In my experience the Axial light controllers work fine when left alone. If you add more LEDs or change the resistance (by adding wire) the controller wont function. I believe its made to function when all the components meet the right specs so any deviation from stock is likely to render it inoperative.

If you like to modify your LEDs these are not the controllers for you.

You should check the connections at the LED, I've had these break loose at least a half dozen times with Axials LEDs. With them on wiggle the LEDs to see if you can get them to make contact and turn on.

 

[Greatscott]

Two things...

First, did you wire them correctly? If you reverse the polarity on an LED (key word: diode), it will not light up.

Second, not likely given that two of the LEDs do light up, did you try testing them with another power source other than the lighting controller (i.e.: plug them directly into the RX)? Most of these system run on 3VDC, if you try plugging them into your RX, which normally is 6VDC or higher, they will burn out.

 

[HumboldtEF]

These have a place to plug in the front lights and the rear lights so one side could still work.

Definitely check the polarity (reverse the wires)

 

[nightcrawler48]

1) As Greatscott says, you can't burn out an LED by reversing polarity, they just won't light up.

2) You don't need to add any resistors when using the Axial controller. All this has been done for you by Axial in the controller.

I assume the 2 red LEDs still work and, as you stated, 2 of the 4 white LEDs work? Did you lengthen all the white LED wires or just the 2 that aren't now working. As all the wires to the white LEDs are black, it is possible you've reversed the wires (polarity) on the 2 LEDs that aren't working now. Try switching the wires on 1 of those and see if it then lights up.

When soldering wires to the LEDs, too much heat can burn out the LED. Don't ask me how I know this . . . . .

 

[food2000]

"In my experience the Axial light controllers work fine when left alone. If you add more LEDs or change the resistance (by adding wire) the controller wont function. I believe its made to function when all the components meet the right specs so any deviation from stock is likely to render it inoperative."

- i think this may have happened.. i lengthen the wire before and it was fine, then i added a lot more and 2 / 4 bulbs didn't light. weird.

"1) As Greatscott says, you can't burn out an LED by reversing polarity, they just won't light up.

2) You don't need to add any resistors when using the Axial controller. All this has been done for you by Axial in the controller.

I assume the 2 red LEDs still work and, as you stated, 2 of the 4 white LEDs work? Did you lengthen all the white LED wires or just the 2 that aren't now working. As all the wires to the white LEDs are black, it is possible you've reversed the wires (polarity) on the 2 LEDs that aren't working now. Try switching the wires on 1 of those and see if it then lights up.

When soldering wires to the LEDs, too much heat can burn out the LED. Don't ask me how I know this . . "

thanks for answering 1 & 2.

i then tested the bulbs both directions after and nothing happened.

I also want to note i was working on this late (11pm) and i can't exactly remember my steps... was sort of a drone state as i thought adding extra length of wire would have been a straight forward procedure.

Maybe i reversed polarity? Either way the 2 bulbs won't as much flicker. I'm going to buy some new bulbs and try to keep it close to stock length from the axial kit.



Can anyone else vouch that the stock axial simple led controller kit shouldn't be tweaked with? seems odd to me that adding wire affects it's function...
*i also don't understand much about resistance...

thanks

 

[HumboldtEF]

Essentially a longer wire has more resistance than a short wire.
https://www.bbc.co.uk/bitesize/guides/z9sb2p3/revision/3

I dont know if this is the case but I have a feeling the way the Axial controller sees that things are in spec is through the resistance. Resistance is effected again by the length of wire, the number of soldered connections and the number of LEDs.

If you've wiggled the LEDs to check for loose connections and reversed the polarity the next step would be to undo the lengthening of the wires just to see if they function with the shorter (stock) length wire, and remember to reverse the polarity if they dont light up on the first try (I like to test before soldering). If its still working maybe the controller can be moved so you dont need the extra length?

 

[food2000]

Essentially a longer wire has more resistance than a short wire.
https://www.bbc.co.uk/bitesize/guides/z9sb2p3/revision/3

I dont know if this is the case but I have a feeling the way the Axial controller sees that things are in spec is through the resistance. Resistance is effected again by the length of wire, the number of soldered connections and the number of LEDs.

If you've wiggled the LEDs to check for loose connections and reversed the polarity the next step would be to undo the lengthening of the wires just to see if they function with the shorter (stock) length wire, and remember to reverse the polarity if they dont light up on the first try (I like to test before soldering). If its still working maybe the controller can be moved so you dont need the extra length?

Wow, great to know.

I will try the above.

Yea.... it's mostly me just wanting to be able to remove the body and set it down further from the chassi when i work on the car. So i added a lot of wire not knowing it's affect on the resistance... i'll install a more conservative amount this time around and test to make sure things are working



thanks again.. totally makes sense now.