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View Full Version : To those using el-cheapo LED strings



Dan Hintz
12-13-2007, 8:31 AM
I've noticed a few threads (here and on other sites) from people using the cheap LED light strings to light up their plexiglass projects. For personal use this is not much of an issue, but please be careful when using them to light up projects for customers (at least ones you might want repeat or word-of-mouth business from).

If the LEDs are socketed (and not directly soldered to the wire), you're going to run into issues in as little as a year. The wires are standard copper, but the LED frames are made from aluminum. Any electrician worth his salt out there knows you can't mix aluminum and copper wiring without special connectors (at least if you expect it to continue working for a long period of time).

I've already had reports from several friends who purchased LED lights last year that the galvanic reaction between the two metals is causing them to rust. Needless to say, two of them that attached them permanently to their houses (because "They're LEDs, they'll never burn out in my lifetime") are none too happy about this. Imagine how unhappy your customers might be when your lit acrylic awards and signs decide to stop lighting about this time next year.

So, if you must include the cheap strings, make sure you get ones that are not socketed... but please don't whine if a bulb fails and you have to cut/solder the string to replace it ;)

James Jaragosky
12-13-2007, 1:05 PM
The lights I referred to are soldered in rather well. In face I cannot tell if the light leads are copper or aluminum due to the solder being applied evenly from supply wire insulation to glass bulb.
I only intend to put these lights into cheap projects $20 to $50 range and they will be fine for that. Also I do not intend to install them in such a way as it would be difficult to replace the whole string which is in fact what I would do for a valued customer. At a cost of less than $4.25 a set I can afford to replace it for a highly valued customer. And as for the rest I do not believe that most people paying $20 for one of my pieces except a lifetime warranty. Heck I just had a $2300.00 lap top die 1 year and 6 days after I purchased it and HP told me sorry your 6 days out of warranty, but we will gladly fix it for $805.00 +shipping both ways. So if one of my $20 dollar customers ever wants the lights replaced, I will gladly do it for a fee, + shipping both ways of course.
I tell people all the time:
1. YOU CAN GET IT FAST
2. YOU CAN GET IT CHEAP
3. YOU CAN GET QUALITY
PICK ANY TWO YOU WANT
BUT YOU CAN ONLY GET TWO OF THESE AT TIME, NOT ALL THREE.
Respectfully Jim

Micheal Donnellan
12-13-2007, 1:37 PM
the reaction may be a problem but I have to agree with James. As most stuff you buy cheap has a 1yr warrenty or no warrenty you or the customer cant expect much for cheap as possible.

ever noticed how things seem to fail within a short time of their warrenties expiring.

Eric Allen
12-13-2007, 5:57 PM
It looks to me like he's not talking about the leads, just the method of mounting. The soldered ones James mentions sound like the preferred method.

Bill Cunningham
12-13-2007, 11:17 PM
The lights I referred to are soldered in rather well. In face I cannot tell if the light leads are copper or aluminum due to the solder being applied evenly from supply wire insulation to glass bulb.


You can't solder copper to aluminum, so it would be copper to copper so it's OK.. Copper to aluminum would have to be a mechanical connection, and as such, prone to corrosion..

Jerry Allen
12-14-2007, 11:03 AM
I have used hundreds of leds and never seen one with aluminum leads.
They are tin plated just like resistors and caps otherwise they would be pretty useless for most applications. When using bare copper wire, it should be tinned before soldering to the led. I have a couple of applications where one lead of the led is soldered and the other end is twisted around a tinned solid wire (a flexible support). They have lasted for years.
I very rarely use sockets because I don't trust them. Having disimilar materials is not the reason they fail. They usually fail due to crappy contact design along with some overheating at the joint. Even copper to copper connections can corrode as you might see occasionally in a wall socket terminal. That is usually due to heat stress, and sometimes because it is not tight, or both.
The other reason is crappy leds.
There are some inferior leds out there. I usually get mine at All Electronics and have never gotten a bad one. Can't say I haven't fried some though.