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Artieiii
08-23-2011, 08:05 AM
I found this link a few days ago so I thought I would share it. I hope this is the right place to post. I did not see an electrical section (non DCC).
This site allows you to calculate the proper resistor based on the voltage and current rating of your chosen LED's and calculates the nearest resistor needed.
http://ledcalc.com/#calc
Here is a screenshot of 1 example i used:
http://i292.photobucket.com/albums/mm22/notashoobie/ResistorCalc.jpg
Keep this link in your bookmarks, you may need it someday!
-Art

gunrunnerjohn
08-23-2011, 09:14 AM
Probably the Technical Model Train Forum would have been a better fit, but this is fine. ;)

tjcruiser
08-23-2011, 09:44 AM
Agreed. I'll move it there.

Nice calculator link!

TJ

gunrunnerjohn
08-23-2011, 10:00 AM
Then there's always the List of electronic color code mnemonics (http://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics) to help you remember what the color codes are for. :)

Artieiii
08-23-2011, 10:07 AM
Then there's always the List of electronic color code mnemonics (http://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics) to help you remember what the color codes are for. :)

I bookmarked that too, thanks gunrunner
I also like that the link I posted is easy to remember www.ledcalc.com this way I can have the guy at radioshack look it up for me if I need it.

-Art

gunrunnerjohn
08-23-2011, 10:14 AM
I've worked with electronics for so long and done so many LED jobs that I just pick an appropriate resistor from the drawer and stick it in. Truthfully, I rarely bother computing the exact current draw, I adjust the resistor for the brightness I desire. I rarely ever run LED's at anything like their maximum current ratings, they end up too bright for most model uses. I've also taken to using the CL2 constant current source for lighting jobs with LED's.

Reckers
08-23-2011, 02:09 PM
I admit personal laziness in this area. I respect the wizardry of our cadre of electronics experts, but I push trains, not volts. I'm content to come on site, display my ignorance and ask someone to suggest what I should use.
In return, however, I do offer advice on bourbon and ponies: I stick to my strong suits!

gunrunnerjohn
08-23-2011, 04:10 PM
Speaking of bourbon... ;)

Reckers
08-23-2011, 05:57 PM
I respect wildlife, too. Especially Wild Turkey.

xrunner
09-19-2011, 06:10 PM
I've also taken to using the CL2 constant current source for lighting jobs with LED's.

I got some of the CL2's today and they work very well, makes it easy to hook up strings of LEDs. I would like to get a higher voltage PS though.

gunrunnerjohn
09-19-2011, 07:18 PM
Well, if you're running this on an N-gauge, you're kinda' limited to the voltage on the track, no?

If you're running DCC, which is really an AC signal, you can use a voltage doubler to jack up the voltage to run LED's. I'm doing this for some passenger cars so they work on conventional 6VAC right through the 18VAC for TMCC.

xrunner
09-19-2011, 07:27 PM
Well, if you're running this on an N-gauge, you're kinda' limited to the voltage on the track, no?


Uh - no.

I'm using LEDs for buildings and other things to come, and I am using another power supply for that part of the system. It has nothing whatsoever to do with the track system.

gunrunnerjohn
09-19-2011, 07:28 PM
OK, in that case, if it's an AC supply, you can use a voltage doubler. Of course, since it's a separate supply, just use a bigger one. :D

xrunner
09-19-2011, 07:40 PM
OK, in that case, if it's an AC supply, you can use a voltage doubler. Of course, since it's a separate supply, just use a bigger one. :D

I have a few power bricks in my junk box from past products that either failed or I lost. The one I have as a prospect is a 12V - 1000mA brick. If that isn't enough current for what I'm planning I can just create another LED bus with another brick/CL2s.

I plan on street lights, building lights, an inspection pit with lights, and even (maybe) a military base (more on that to come) with blue landing strip lights.

Lights, lights everywhere.

gunrunnerjohn
09-19-2011, 07:55 PM
Well, 1 amp will light a bunch of LED's! If you go for maximum output, that's 50 of them. Truthfully, for many purposes, that's far to bright, so you'll probably be able to light 100 or more in real applications.

xrunner
09-19-2011, 08:00 PM
Well, 1 amp will light a bunch of LED's! If you go for maximum output, that's 50 of them. Truthfully, for many purposes, that's far to bright, so you'll probably be able to light 100 or more in real applications.

Oh, did I mention the football stadium?

Just kidding ;)

xrunner
09-20-2011, 08:36 AM
Does anyone have any pics of LEDs used in your layout? I'd like to see how you are using them for various things.