81Views3Replies

Author Options:

Running LEDs? Answered

Quick question, really.
Anyone know if it's possible to run LEDs in series straight off of wall current? 
For instance, lets say I have 60 2v LEDs connected in series. Could I just put 120 VAC into them (with the proper resistor of course) and they'd light up with no problem?

3 Replies

user
frollard (author)2012-05-01

technically, yes - but remember, 120vac out of the wall is actually 180 volts peak to peak (sine curve), so plan your voltage around the 180v.

There is an instructable or six about running leds on line voltage.

Beating head against wall now: It's dangerous, really dangerous, as line voltage tends to kill you.

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)frollard2012-05-01

Stick to the RMS value, IMHO, the 1.4 x RMS won't hurt, so to speak.

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)2012-05-01

Yes, it can be done, but you have to be careful about the reverse voltage rating of the LED. Its a good plan to rate them for half as many LEDs, and wire two, anti-parallel strings - you only need one resistor.

Steve

Select as Best AnswerUndo Best Answer