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Help with adding LED's and mini fan to existing circuit.

Hello, and thank you in advanced for taking the time to read through this and give me feed back. I greatly appreciate it.

So I have a working circuit that is running off a 3 prong 120 V AC 10 amp power supply. I thought i would pretty it up by adding a led lit power switch and another plane led in a different spot, and make it a bit more reliable by adding a fan on the inside of the enclosure. I downloaded and app that calculated how much Resistance I need from the power supply to each led and fan (all in parallel). After i hooked everything up to what i thought would be an easy mod. to my surprise I smoked the resistors in under 60 seconds.

I talked to a friend who gave me some basic direction but couldn't give me technical stats. He said i needed to start with a transformer (i believe is the term he used) to drop the voltage, then to go to a bridge rectifier to turn the AC current into DC, then after that i would need a current regulating switch to give the proper supply for the LED's and Fan. Then from there he said i would be able to calculate the Resistance needed for each Led and fan and would be able to hook up the resistors needed with out damaging them. If this is the correct steps to take I can understand that; however, he was not able to give me any technical info on any of these components and what i would require.
If these steps are correct, what i need help with is to determine what specs i would need for each piece, Including the resistors after the current regulating switch.

(Technical Info) The 1st LED im using is a Switch that lights up when on and has leads just for the LED (the switch is already being used and works). I could only find the style i wanted from an automotive shop so it says for the led 12V only(unfortunately i couldn't find specs on the amperage the LED takes, but the switch itself is rated at 5amps). The second Led is a basic Green Led that i Purchased from radio shack, It is 2.1 V and runs on 30 MA, The fan im using is from an old game console and is 5V and runs on 80MA.
Thank you for any and all help you give, this went from what i thought was an easy stylish mod to me ripping my hair out and scouring the internet for info, i finally gave up and decided to join this great community to ask for help with my specif conditions.

Thanks Instructable Fam.!

Downunder35m2 years ago

Let me be clear and maybe a bit harsh but it you have no idea about basic electrics and electronics you should not play with it!

From what I read here I would feel very bad giving you detailed instructions on how to fix the problem as would have to fear you execute yourself in the process or burn the house down during testing.

To run a LED from your mains you need more than just a resistor and it won't fit into an existing switch.

The only safe option I see is to buy a suitable power supply for the fan that is externally connected and to use ready to go switches with light already built in.