lights, led's, resistors

[runLoganrun]

Hi,

i want to run a series of led lights, i guess off a 5v line, prob 6 lights.

does each light need a resistor (100 om?), or is it that i can put higher rated resistors on several lights?

where exactly does the resistor go on the light, or where in-line with multiple lights?

related question: vandal switches say rated ~3.4-12v, does that mean you can put 12v straight to the led on that switch, or do they just mean the pass through current?

Thanks!
rlr

 

[zaxour]

a single resistor will limit the current and it doesn't matter which order you put them in the series. The resistor's purpose is to obviously limit the current.

 

[MrF]

does each light need a resistor (100 om?)?

Not necessarily. If you want to put all the LEDs in series, you only need one resistor.
But, if you want different brightness, you need to place the LEDs (or some of them or some combination of them) in parallel. Then, each parallel branch needs a resistor.

related question: vandal switches say rated ~3.4-12v, does that mean you can put 12v straight to the led on that switch, or do they just mean the pass through current?

Think of a very high voltage like 10kV. You cannot use a tiny switch to disconnect such a high voltage or else, it will spark across the switch. The voltage rating of a switch is the voltage you can safely disconnect with it.