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I need to find a 7VAC LED(?)

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Fozzy The Bear:


--- Quote from: whammoed on April 30, 2008, 10:48:30 am ---
--- Quote from: Fozzy The Bear on April 30, 2008, 06:06:07 am ---Guys Guys Guys!!! Please!!!

All LED's work perfectly well on AC Voltages......

--- End quote ---

I think that's a little misleading.  You can run LED's from AC if set up properly.  LED's are indeed diodes but I don't think they are really good at the diode part...just the light emitting part.

--- End quote ---


A few years ago this was true..... But at AC 7V with a current limit on it, it's not going to hit breakdown. Modern ones work quite well now from the reverse breakdown point of view. To be honest you'd still be putting a current limit resistor in the circuit anyway and there probably already is one. Not to mention that this circuit he's attaching it to was already designed with exactly this application in mind and had an LED already on it. So it's unlikely to be any sort of a problem here.

Best Regards,
Julian (Fozzy The Bear)

whammoed:

Granted, but you said "on AC Voltages" and not "on 7VAC in this case" or something similar.
Also I have noticed an issue with heat buildup when running directly on as little as 12VAC.  Heat will shorten the LED's lifespan.
I'm not disagreeing with you, just trying to keep someone from hooking up LEDs improperly to their mains power, etc...

Fozzy The Bear:


--- Quote from: whammoed on April 30, 2008, 12:19:59 pm ---Granted, but you said "on AC Voltages" and not "on 7VAC in this case" or something similar.
Also I have noticed an issue with heat buildup when running directly on as little as 12VAC.  Heat will shorten the LED's lifespan.
I'm not disagreeing with you, just trying to keep someone from hooking up LEDs improperly to their mains power, etc...

--- End quote ---

Oh! Agreed mate!..... It's just that I kind of assumed that what I'd said was in the context of exactly this application.  12V AC will indeed fry most LEDs But then the vast majority of LED's have a forward voltage rating well below that in any case. So unless it was someone who was a total dufus they wouldn't go connecting it to the full mains voltage anyway...  Mind you I do recall somebody connecting a 12V LED strip directly to the mains and then ranting on here at Randy Turner because the blue smoke fairy escaped from inside the little lights.

Best Regards,
Julian (Fozzy The Bear)

whammoed:


--- Quote from: Fozzy The Bear on April 30, 2008, 03:49:04 pm ---
Oh! Agreed mate!..... It's just that I kind of assumed that what I'd said was in the context of exactly this application.  12V AC will indeed fry most LEDs But then the vast majority of LED's have a forward voltage rating well below that in any case. So unless it was someone who was a total dufus they wouldn't go connecting it to the full mains voltage anyway...  Mind you I do recall somebody connecting a 12V LED strip directly to the mains and then ranting on here at Randy Turner because the blue smoke fairy escaped from inside the little lights.

Best Regards,
Julian (Fozzy The Bear)

--- End quote ---

I figured you might mean in that context, but I didn't think everyone would read it that way.
I get a lot of questions from customers that simply don't know anything about this sort of thing, so I've cime to realize there are a lot of people out there that are just starting to get a basic understanding of anything electronic...even people interested in BYOAC.

fjl:

I still doubt its an LED. It will light up like the rest of you said but LEDs where not originally meant to be used on AC Voltages. AC will break down the component LED a lot quicker than DC voltage. So it's life span would be greatly reduced. So unless this was bad engineering, then perhaps they've come out with diodes that where made for AC.
 :dunno

Hey Jasonbar, how about a good close up pic of this LED?

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