powering led's

El-Scotto

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Joined

Sep 3, 2003

Location

PA

• Aug 18, 2004

• #1

how easy and expensive is it to rig something up to battery power led's? i have a wall clock that im gonna mess around with and want to cut some parts of it off and light the numbers and hands up with some leds and acrylic. sooo anyhelp would be appreciated

 

greenman100

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Joined

May 18, 2003

Location

trying to keep all the magic smoke in

• Aug 18, 2004

• #2

very easy, get the polarity right

do a search on the forums or google, the answers are out there

come back if you need more help.

 

vonkaar

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Joined

May 20, 2003

Location

Colleyville, TX

• Aug 18, 2004

• #3

Longer leg is positive, shorter leg is negative. You can also tell by the 'notch' on LEDs. Notched side = positive.
That's about it =p. All else is voltage. AA = 1.5v, two in series = 3v, which is what common LEDs run off of.

 

greenman100

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May 18, 2003

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trying to keep all the magic smoke in

• Aug 18, 2004

• #4

also different colors have different nominal voltages

~2.4v for red, ~4.5v for blue IIRC

 

neonblingbling

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Joined

Aug 8, 2004

• Aug 18, 2004

• #5

nicd and nimh batteries give off 1.2 volts.... might be helpful for the red leds.

 

greenman100

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Joined

May 18, 2003

Location

trying to keep all the magic smoke in

• Aug 18, 2004

• #6

yes

-->but now you need a charger for those batteries, too.

a resistor is another option

 

vonkaar

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Joined

May 20, 2003

Location

Colleyville, TX

• Aug 18, 2004

• #7

greenman100 said:

also different colors have different nominal voltages

~2.4v for red, ~4.5v for blue IIRC

Click to expand...

commonly, yes... but can get both in either voltages.

 

vonkaar

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Joined

May 20, 2003

Location

Colleyville, TX

• Aug 18, 2004

• #8

Oh, and the operational voltages have a fairly wide range... 2.25 to 3v, for example.