Go Back   RCCrawler Forums > RCCrawler General Tech > Electronics
Loading

Notices

Thread: What size resister for LED's

Reply
 
LinkBack Thread Tools Display Modes
Old 12-21-2010, 09:40 PM   #1
Rock Crawler
 
Join Date: Nov 2010
Location: Denver
Posts: 591
Default What size resister for LED's

I would like to know what you folks recommend me to get for a resister for wiring up some LED's hooked up to a 9v battery.

Thanks
0lllllll0 is offline   Reply With Quote
Sponsored Links
Old 12-21-2010, 09:47 PM   #2
Pebble Pounder
 
Join Date: Jan 2010
Location: YYZ
Posts: 141
Default

It depends on what wattage LED you want.

1W or higher will require heatsink aswell...

If you don't need super bright light to illuminate the night but just want a small light... just get yourself one of those LED Light clip on for caps. Those come with 5 LEDs and usually run at 3v. So you can get it out of it's casing and do the wiring to how ever you want... power it with 2xAA.
xxgg is offline   Reply With Quote
Old 12-21-2010, 09:56 PM   #3
Rock Crawler
 
Join Date: Sep 2004
Location: eureka
Posts: 577
Default

http://ledcalc.com/#calc
yoda316 is offline   Reply With Quote
Old 12-21-2010, 10:01 PM   #4
www.team3sixrc.com
 
Join Date: Mar 2008
Location: Scalerville
Posts: 4,506
Default

Needed that, thanks.

Quote:
Originally Posted by yoda316 View Post
team3six is offline   Reply With Quote
Old 12-21-2010, 10:05 PM   #5
RCC Addict
 
Join Date: Jan 2004
Location: Gunbarrel
Posts: 1,167
Default

another good link here
Rogue is offline   Reply With Quote
Old 12-21-2010, 10:08 PM   #6
Rock Crawler
 
Join Date: Nov 2010
Location: Denver
Posts: 591
Default

I will be wiring 3w LED's. I want to use a 9v battery to power them and have the hooked to a switch. Probably no more than 10 on one switch.

Any recommendations for someone ignorant to all this electrical stuff like me? A simple wiring diagram that a lei man can figure out would be great too.

Thanks
0lllllll0 is offline   Reply With Quote
Old 12-21-2010, 10:12 PM   #7
Rock Crawler
 
Join Date: Nov 2010
Location: Denver
Posts: 591
Default

Quote:
Originally Posted by Rogue View Post
another good link here
That is a cool site, but how do I know what the "diode forward voltage" is, and the "diode forward current (mA)"?

Thanks
0lllllll0 is offline   Reply With Quote
Old 12-21-2010, 10:42 PM   #8
I wanna be Dave
 
Join Date: Sep 2008
Location: four o six
Posts: 2,101
Default

should say on the paper work with your LEDs...or on the site you picked them up from..
squatch71 is offline   Reply With Quote
Old 12-21-2010, 10:51 PM   #9
Pebble Pounder
 
Join Date: May 2010
Location: Indianapolis
Posts: 149
Default

Its really not as simple as saying maybe 3 or maybe 10 led's from a 9 volt.

If they are different colors, the voltage requirements will probably be different.

If you can come up with a pot, like a volume pot, (variable resistor) that does lower ohms, then hook up your LED's and 9 volt with the pot in series and adjust it to where they just come on and start to get bright.

OR

hook everything up except leave one side of the battery open, and hook up different resistors until they just start to get bright.

I have 4 led's in series on one of my cars with 160 Ohm resistor in series to the 9 volt. It is 2 red and 2 blue LED's. The blue one's are dimmer than the red one's because of their nature, but If I lowered the resistance there might be a chance of blowing out the red one's.

If you want some white ones for head lights and some red ones for breaklights and this and that, you might as well purchase a LED controller made for the job. It gets complicated.

Hope that helps
nandrewjackson is offline   Reply With Quote
Old 12-22-2010, 11:47 AM   #10
owner, Holmes Hobbies LLC
 
JohnRobHolmes's Avatar
 
Join Date: Nov 2004
Location: Volt up! Gear down!
Posts: 20,290
Default

Sounds like an LED driver would be a good bet for your situation. Here is a neat little one I ran accross. You won't need resistors. http://holmeshobbies.com/product.php...&cat=13&page=1
JohnRobHolmes is offline   Reply With Quote
Old 01-22-2011, 03:34 PM   #11
Newbie
 
Join Date: Apr 2010
Location: Norway
Posts: 42
Default

I'm using this one ;) http://www.hebeiltd.com.cn/?p=zz.led...tor.calculator Nice name btw ;)
OllllO is offline   Reply With Quote
Old 01-30-2011, 12:37 AM   #12
Rock Stacker
 
Join Date: Jan 2011
Location: Yakima
Posts: 59
Default

Thanks Everyone! Awesome info.
new2this is offline   Reply With Quote
Reply



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 08:58 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2014 RCCrawler.com