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Rear light problem,Help required
Posted: Sun Sep 08, 2013 9:06 pm
by marksim
Hi guys,
really could do with some help here.
Ive a different seat unit fit on my KR1 and therefore have a small LED Stop & Tail rear light.
My problem is they dont last very long and after 3 different ones im at a loss what to do next.
It seems after a while several of the LEDs stop working and when ive taken the lights apart it seems as though some of the small resistors have burnt outr.
Have any of you got any ideas why ?
Thanks in advance
Re: Rear light problem,Help required
Posted: Sun Sep 08, 2013 9:32 pm
by 500bernie
Hi Mark,
Sounds like you need to sort out the correct value resistors to suit your leds and your supply voltage.
You can calculate this using the following formula:
R = (V1 - V2) / I
Where;
V1 = power supply voltage
V2 = LED voltage
I = LED current (usually 20mA which is .02A - check the spec of the ones you are using)
Cheers
Bernie
Re: Rear light problem,Help required
Posted: Sun Sep 08, 2013 9:55 pm
by marksim
Cheers Bernie,
the problem is the 3 different units ive tried have had various amounts of LEDs and the resistors are built into their circuit boards.
Just checked the info with the adverts and it says they come with the correct resistors for the flash rate
Ive also fit these to other bikes and had no problems ?
Re: Rear light problem,Help required
Posted: Sun Sep 08, 2013 11:35 pm
by 500bernie
Hi Mark,
You should check the supply voltage to the units (and the integrity of the earths while you are at it).
Normally LEDs and their circuits are quite forgiving in relation to fluctuation in supply voltages (within reason).
It is most likely something daft like a poor earth, causing you to draw excess current through one or more of the units (i.e. when you are braking with your lights/indicators on). A fun way to spend a few evenings
Good luck [-o<
Re: Rear light problem,Help required
Posted: Mon Sep 09, 2013 7:54 pm
by marksim
Cheers Bernie
I also run a LED headlight if that helps you anyway in sorting the problem LOL
Re: Rear light problem,Help required
Posted: Sat Sep 21, 2013 12:05 pm
by BradfordWebster
marksim wrote:Hi guys,
really could do with some help here.
Ive a different seat unit fit on my KR1 and therefore have a small LED Stop & Tail rear light.
My problem is they dont last very long and after 3 different ones im at a loss what to do next.
It seems after a while several of the LEDs stop working and when ive taken the lights apart it seems as though some of the small resistors have burnt outr.
Have any of you got any ideas why ?
Thanks in advance
There is some issue with resistors..Just get correct ohm resistors for proper functioning of these lights..