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How do I wire and power a simple LED circuit? Answered

I'm trying to create a sign with letters made of 40 10mm LED bulbs. They come pre-wired with individual resistors and only say they require 9v-12v at 20mA.

Here is a link: http://www.ebay.com/itm/10pcs-10mm-White-Diffused-Round-Pre-Wired-LEDs-Light-9V-12v-USA-/111795082716?

I would like to wire them in a parallel circuit. I'm also trying to power a single red LED of the same variety, but have read that because the draw can be different I shouldn't wire it to be the 41st bulb in the parallel circuit. It too comes with its own resistor:


I'd like to be able to power these 41 bulbs with a single power source, and integrate a rocker switch to turn the fixture on and off, will I need to a specific switch for this? How should I wire the LEDs? Can I connect the series straight to a 12v power source because each bulb has a resistor? 



3 years ago

I didn't see or read there was a resistor in series, except by inference.

There has to be a resistor to operate an LED at 9-12VDC.

Follow Ricks good advice..

Use any rocker switch for AC lighting or a smaller rocker that can switch 24_Volts or more and 2_Amps or more

Be sure to click on the picture to see the whole image...


3 years ago

1. You will need a power source that can provide 1 Amp - 41 * 0.020 amps is 0.82 amps.

2. Yes as they all have their own resistor you can wire in parallel.

3. Ensure the polarity is right for each LED.

4. the LEDs will draw what ever current they need from the supply.

add the red to the end it will be ok and draw what it needs as long as it operates off the same voltage.

caveat: I didn't look at the LED spec - no time this morning. - so I assume your statement is correct.