dominic_2005 Posted November 15, 2017 Share Posted November 15, 2017 Hiya folks. Quick question regarding resistance from someone who's knowledge of electronics is limited to + is positive, - is negative. I am planning a lighted build, in parallel. All LED's are 3.2v each with an individual resistor to run from a 12v power source. If I was to use, say two strips of copper to act like a power rail for each LED to be connected to, would the thickness/width of said copper affect the result? IE, if it is too thick is it going to cause the LED's to be dimmer than just using cables? Hope I explained that? Thanks D Link to comment Share on other sites More sharing options...
Bozothenutter Posted November 15, 2017 Share Posted November 15, 2017 other way around...too thin.....waaaaaayyyyyy to thin might increase resistance. nothing to worry about Link to comment Share on other sites More sharing options...
dominic_2005 Posted November 15, 2017 Author Share Posted November 15, 2017 (edited) I hate electronics lol So If I was to use 1mmx3mm copper strip, it's not going to give me a brightness reduction? Or even 2mm copper wire...basically something thick enough to hold it's shape is what I am looking to use ideally. Thanks D Edited November 15, 2017 by dominic_2005 Link to comment Share on other sites More sharing options...
colin Posted November 15, 2017 Share Posted November 15, 2017 The thickness will depend on how much total length you intend to run to supply the led's, to be honest I would think any off the above will be fine unless your using hundreds of led's and one hell of a conductor run Link to comment Share on other sites More sharing options...
bhouse Posted November 15, 2017 Share Posted November 15, 2017 It all depends... How many LEDs? Do you know what current they draw? Alternatively, what resistor are you using on each LED? Link to comment Share on other sites More sharing options...
dominic_2005 Posted November 15, 2017 Author Share Posted November 15, 2017 (edited) 11 minutes ago, bhouse said: It all depends... How many LEDs? Do you know what current they draw? Alternatively, what resistor are you using on each LED? Off the top of my head, will be around 170-180 LED's. Most of them are pre-wired/pre-resistored to run off 12v. On top of that, about 30-40 will be manually fitted with a 470 Ohm resistor each. (Bought on advice). Edited November 15, 2017 by dominic_2005 clarification Link to comment Share on other sites More sharing options...
bhouse Posted November 15, 2017 Share Posted November 15, 2017 Ooh that's a lot. It looks as if you could easily need 4 amps or so to power that lot. That means that a PP3 9V battery would last for about 15 minutes. Another point is heat build-up. If all the LEDs are close together in an unventilated space you may well have problems with heat build-up. I wonder if you'd be better off going for fewer LEDs and using fibre optic cable to get the light to where it's needed? If you plan to go ahead with the LEDs, there's a really good website that explains all the ramifications far better than I could! Link to comment Share on other sites More sharing options...
dominic_2005 Posted November 15, 2017 Author Share Posted November 15, 2017 Fair few huh? I will be running it from a mains 12v DC power supply. I ran my Aida Luna using the same method and that had around 150-ish LED's: I am already planning on using fibre-optics as well. There may not end up being that many bulbs in, thats how many i've ordered. But then there are 12 LED's just for the floodlights around the external hull below the lifeboat deck lol. 3 Link to comment Share on other sites More sharing options...
dominic_2005 Posted November 16, 2017 Author Share Posted November 16, 2017 OK, I will never ever understand electronics. I was just playing about with ideas, and I took 3 LED's. 3.2v 20mA @ 12v I connected each one directly to the power source (Parallel) and as should be, they were all the same brightness. I tried those same 3 LED's in Series, and...they still all lit up the same brightness. By rights, only the first one should have been fully lit, the 2nd and 3rd should have been slightly dimmer. Link to comment Share on other sites More sharing options...
bhouse Posted November 16, 2017 Share Posted November 16, 2017 45 minutes ago, dominic_2005 said: OK, I will never ever understand electronics You will if you read that guide I linked to! Link to comment Share on other sites More sharing options...
dominic_2005 Posted November 16, 2017 Author Share Posted November 16, 2017 (edited) I did read it. I didn't understand much of it, but I got the basics. My problem is my experiences always counter that which every piece of information I read tells me...hence, I will never understand it lol Also, I don't get the difference between fact and opinion of the writer. EG: One article will say "oh never ever put LED's in Parallel" ... whilst another says Parallel is required in order not to limit the number of LED's to the amount of the power source. As I understand it, and by all means correct me if I am wrong, if I had, say 10 3.4v non-resistored LED's and I wired them in series, I would need a power supply of 34v. However, I could add a resistor to each one of those 3.4v LED's and run them in parallel from a single 12v power supply. Edited November 16, 2017 by dominic_2005 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now