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Inf4mous
01-07-2016, 06:02 PM
Hey guys so im building my LED string, its 10 segments of 10 LED's.... So 100 of them..they are wired in Parallel i used the LED Calculator and it says i need a 1ohm 4 watt capable resistor. Is that correct? if it is can i use a 1 ohm 10 watt resistor? my local radio shack doesn't have the 4 watt one


LED Specs: 5mm, 3.2-3.4v, 20mA

Battery: 3.7v Lithium Ion 18650

Thanks

Miraluka
01-07-2016, 09:25 PM
That LED calculator always rounds up to at least 1ohm but you don't need more than .5ohm. (even that is more than you need) 4 watts is right, and 10 watts would be fine as long as it fits in your build.

Inf4mous
01-08-2016, 11:17 AM
That LED calculator always rounds up to at least 1ohm but you don't need more than .5ohm. (even that is more than you need) 4 watts is right, and 10 watts would be fine as long as it fits in your build.

Sweet, thanks! also this is such a noob question but ive heard multiple answers to this and im a little confused.. Does the Resistor go on the Positive side or negative side cause ive been told both so idk which to do.

Silver Serpent
01-08-2016, 11:45 AM
Resistors can go on either side.

Exception: If you're using a DynaOhm resistor for an accent LED, it must go on the positive side.