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soakes94
08-21-2010, 08:35 AM
Hey :) I was wondering if someone could tell me if the following LEDS are any use or if I'm wasting my money, I'm not planning on using them in floodlights or anything, but I'm going to use them in a square piece of electric conduit, they dont need to be really bright like the ones in a floodlight, but bright enough to be seen and it to be obvious that they are on.

Red leds (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=300455232621&ssPageName=STRK:MEWAX:IT)
Green leds (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=300449409283&ssPageName=STRK:MEWAX:IT)
Blue leds (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290459368020&ssPageName=STRK:MEWAX:IT)
Amber leds (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290463966923&ssPageName=STRK:MEWAX:IT)
White leds (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290465448433&ssPageName=STRK:MEWAX:IT)

Thanks :)

dirknerkle
08-21-2010, 08:47 AM
They look like generic LEDs and they'd probably work fine. Be sure to order the proper resistor depending on whether you're going to power them with either 5v or 12v. Putting the 12v resistor on using 5v will work but it won't be quite as bright. Putting the 5v resistor on using 12v will cause them to be brighter but may burn them out, too. It's not a bad buy -- 100 LEDs for about 4 to 5 cents each.

soakes94
08-21-2010, 08:54 AM
I will probably buy separate resistors so I can wire them in a series, the reason I wanted to check is I once bought cheap leds like these and used them in a floodlight, I had 20 of each color so I had 60 leds in total and I had made a floodlight with 12 of each color but they were more expensive and my floodlight with 12 leds was alot brighter than the 20 led floodlight lol

dirknerkle
08-21-2010, 09:02 AM
If you're wiring them in series you won't need a resistor on each LED. You'll have to calculate what you need depending on how many LEDs you'll put in series. The ones you're looking at have varying forward voltages, which is normal for different colors, so calculate carefully if you're planning to mix and match them.

soakes94
08-21-2010, 09:24 AM
Okay will do, I have made this kind of thing before with the expensive leds that I used in the floodlights and they came out great :)

dirknerkle
08-21-2010, 01:36 PM
Okay will do, I have made this kind of thing before with the expensive leds that I used in the floodlights and they came out great :)

Good deal. Be sure to document and photograph what you're doing and post it here somewhere -- others will be interested!

soakes94
08-21-2010, 03:09 PM
Good deal. Be sure to document and photograph what you're doing and post it here somewhere -- others will be interested!

OK will do assuming I find the money lol

P. Short
08-21-2010, 09:28 PM
My feelings on this are fairly well known...I don't really trust either the quality of the E-Bay parts nor that they meet specifications. My suspicion is always that all or most of the LEDs on Ebay are manufacturing rejects that have made their way onto the market somehow or other...no way to prove it, of course.

scorpia
08-22-2010, 05:49 AM
My feelings on this are fairly well known...I don't really trust either the quality of the E-Bay parts nor that they meet specifications. My suspicion is always that all or most of the LEDs on Ebay are manufacturing rejects that have made their way onto the market somehow or other...no way to prove it, of course.

All of which may well be true, but it doesnt mean that they work any worse for our use than full price perfect spec leds as all we are doing is what ends up being pretty simple blinky flashy.

LabRat
08-22-2010, 06:07 AM
All of which may well be true, but it doesnt mean that they work any worse for our use than full price perfect spec leds as all we are doing is what ends up being pretty simple blinky flashy.

Agreed. Caveat Emptor (Buyer Beware)

My last "flood" population exercise was interesting, as I discovered a large % of my blue leds had the legs reversed. Had I not been testing everyone of them with a battery first, it would have been a *long* night of debugging to track things down.

Edit: Clarification - these were 5mm blues purchased in bulk. NOT part of any co-op purchase.

LabRat
08-22-2010, 06:09 AM
Removed... posted to the wrong forum.

soakes94
08-22-2010, 10:49 AM
I wouldn't be using them all so if any were to burn out I could replace them, I just hope they don't burn out if I ever have the final product at my school cause burnt leds stink and I might set of a smoke detector lol

P. Short
08-22-2010, 11:45 AM
I don't think that I've ever had LEDs literally 'burn up'. Instead, they just stop working.

budude
08-22-2010, 11:58 AM
I recall popping the tops off a few of them back in my college days - don't recall what I was doing to them...

I've purchased quite a few LEDs from bestshop2008hk who have an eBay store - not saying their quality is any better or worse but they have a good selection and the prices are usually pretty good.

StandingInAwe85
08-22-2010, 02:52 PM
I've purchased quite a few LEDs from bestshop2008hk who have an eBay store - not saying their quality is any better or worse but they have a good selection and the prices are usually pretty good.

I'm actually considering buying 2,000 of the wide angle 5mm blue ones from them for my LEDTriks, can you make any comment about their products or service? It'll be a roughly $95 investment so any input is appreciated.

I'm looking specifically for color consistency; I already bought some from LEDShoppe (website, not ebay) to use for it and the colors between the bags vary way too much to use on the sign... they're about to become some really nice floodlights though.

budude
08-22-2010, 03:49 PM
I've purchased the cheap Red LEDs for my LEDTriks - 4,000 of them - not a single bad one in the bunch. It's hard to judge the consistency unless you get all 3,072 LEDs perfectly aligned to each other. I would just say they're good enough for use with the LEDTriks anyway. I also got a selection of SuperFlux and normal 4-lead RGB LEDs and they look pretty good as well.

Entropy
08-26-2010, 09:51 AM
I'll probably be making an order from Topbright when I return from my business trip. They seem to have pretty good feedback.