Post by Deleted on Apr 1, 2007 17:38:49 GMT
The following is taken from a thread which details the lighting on a 1/24 scale Peterbilt Wrecker elsewhwre on this forum: ipmsuk.proboards20.com/index.cgi?board=roadtransport&action=display&thread=1173560071 lighting tips and diagram courtesy of 'Lightman' ... freespace.virgin.net/model.town/
"With reference to the lighting, Merlin is quite correct, running LED's in series depends on the LED voltage and the supply voltage, a typical example is--
You must add the forward voltage of all your LED's to get the correct power supply ie, if your using 2.2v LED's on a 9v supply, you can only use x4 LED's in series which are equal to 8.8v, this has a minus voltage of 0.2v in respect of the 9v supply which is fine, adding more LED's on the series will result in a lose of brightness to the bulbs.
Now, the problem with using x4 bulbs on a 9v supply in series is that, if one of the bulbs goes down, this will take out all the other bulbs faster than you can say 'Oh crickey' which is not good as all your hard work has to be redone, the reason for this is because with the one bulb down, the x3 bulbs left will now be drawing 3v each, more than the forward voltage.
The easiest way of building a string of LED's and provide the same brightness is to add resistors to each bulb and loop the negative to each negative leg on all the bulbs (Short leg), then loop the input voltage to each positive leg (Long leg)"
"With reference to the lighting, Merlin is quite correct, running LED's in series depends on the LED voltage and the supply voltage, a typical example is--
You must add the forward voltage of all your LED's to get the correct power supply ie, if your using 2.2v LED's on a 9v supply, you can only use x4 LED's in series which are equal to 8.8v, this has a minus voltage of 0.2v in respect of the 9v supply which is fine, adding more LED's on the series will result in a lose of brightness to the bulbs.
Now, the problem with using x4 bulbs on a 9v supply in series is that, if one of the bulbs goes down, this will take out all the other bulbs faster than you can say 'Oh crickey' which is not good as all your hard work has to be redone, the reason for this is because with the one bulb down, the x3 bulbs left will now be drawing 3v each, more than the forward voltage.
The easiest way of building a string of LED's and provide the same brightness is to add resistors to each bulb and loop the negative to each negative leg on all the bulbs (Short leg), then loop the input voltage to each positive leg (Long leg)"