In general, if a light has say 3 leds, are the leds drawing power in series or in parallel? I'm spesifically interrested in the way my Osram Crosser 3-led spotlight operates. The reason is that I want to extend my runtimes when I don't need it at its full brightness. I want to install a seperate switch to disable 2 of the 3 led's in order to run the light on only 1 of its 3 led's most of the time.
I can only do this if the led's operate in parallel. Any suggestions is welcome.
Currently I power it with 2 packs of 3XNimh's in parallel. The light originally works woth 4X D-cell alcalines. If I give the light 4X nimh's the light is much brighter, therefore I only use 3X AA's because I fear the led's might burn out sooner on 4XAA's.
some pics of how the leds are arranged willhelp..
or u can tr to find it..
ur source voltage is 3.6 typical..
check the volts accross each led.. if its 3+ volts AND ur ligght has no Boost circuit then they are most probably in pasrrallel.. otherwise they may be in series..but with 3.6 vollts max at source its most likely that they r in parrallel.. u can install and push button or jumper in the path of spome lds ands turn them on/off at will..
I made some comments based on an assumption that you might have a series wired LEDs but after re-reading the first 2 posts I'm thinking they might be parallel and will wait until further investigation to comment. If they are in parallel, then most likely its a voltage controlled driver and if that is the case, you could easily take one of the LEDs out of the circuit to cut back on power.
measure the voltage difference at cathode of one and anode of the next consective led if its 0 then they are in series.. do this when its turned on,, but take care not to create a short somewhere...with ur probbes...
alternativly u can try measuring resisytance between the cathode/anode of one to anode/cathode consectively of the immediatly next le.. if the resistance is 0 ohm the its probably in series... do not assumne anything ..do test and verify for every case..
On the other side, if they are in series not one will work if I break the circuit, which means at least I can't fry anything. I will do this mod this weekend.
the if is big...if they are in series and u break any of contact then yes u wont damage anything.. but without looking at ckt i cant say it for sure..also if they are in parrallel and u break one contact and the others lit.. u wont do any damage except the leds will be operating for spec...so if that happen just turn off to minimize the time for over running...no more then few seconds for led longevity...