Introduction: A Guide for Buying LED's on E Bay

Picture of A Guide for Buying  LED's on E Bay

I have had a number of people ask about where to get the LED's that I used in my recent instructable,

Rather than just give a link to something I thought it would be better to share some of what I have learned about the new LED's that have been coming up for sale and the process of buying them on E Bay.

I will provide links here but because the listings on E Bay are constantly changing I have no idea for how long any of them will be valid.

In order to avoid being thought of as spam I am not going to recommend any one company to buy from. I, in fact, have bought from many, it all depends on who has the best deal at the moment. The ones I am showing should be thought of as examples of what is for sale. You should do a search at the time you are thinking of buying so you can get the best price. E Bay is a very fluid place and you need to learn how to go with the flow in order to get the best deals.

Step 1: Type

Picture of Type

There is a myriad of LED's out now. The specific ones I used for my light were in a strip arrangement. They are mounted in modules with varying numbers of LED's and varying colors and wired together in parallel and held together with double stick tape. The tape holding them can be cut and the modules can be spaced out in a string. The basic types of LED's are white, either warm white or daylight, and RGB which stands for Red Green Blue. RGB can be made to appear as any color using a controller to mix the colors.

RGB's are usually limited to just 3 LED's per module. They have 4 wires connecting them, one for power and then 3 others, one for each color. In order to work correctly you HAVE to use a controller. If you buy a strip with an included controller then you have no problem. If you buy a strip alone you will need to get one for it. The good news is that you can control many strips with just one controller.

I made it a habit to test each strip as I received them and discovered that they are not all wired the same. The power is always the same but sometimes the color wires don't control the color they are. So one strip will be green and the other red. This is really annoying but also really good to know BEFORE you solder everything together. Always test them to find out which color is which.

RGB's are more expensive than single color. And I can understand that. They take more work to wire them up.

Step 2: Number

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The first strip I bought was a single 3 light strip of 20. I wanted to see what they were and what they could do. I had seen (and bought) the long string of LED's but these strip ones were new to me. The 3 LED's per module was pretty standard. Then some with 5 showed up and lately some with 6. There is a square one that has 4, either in one color or RGB. The most so far that I have seen has been 6 LED's on one module. All the modules always require 12 volts no matter how many LED's they have.

Keep in mind that the more LED's there are the higher the power requirements to run them. For some things the 3 's work great. But if you need more light then the higher number might work. The more LED's per module, the more they cost.

There is something strange going on with the power requirements. The manufacturer often gives a number of watts for each individual LED. But in experimenting with them the numbers don't add up right. Now I have been seeing disclaimers from the sellers that the manufacturers numbers don't add up and that you can't rely on the wattage being what they say. So no body appears to really understand just what the ratings are. I used my own meter and went by that. Basically if the power supply you are using doesn't overheat then your OK. If it does then you need a bigger power supply.

The number that you often see in the description refers to the physical size of the LED's. The 5050 LED is the larger brighter one. I avoid the smaller ones. Most of the strips have 5050 LED's. A lot of the long strings have smaller LED's because they are not intended for lighting as much as decoration.

Step 3: It All Comes From China

Picture of It All Comes From China

Almost all of the LED's being sold on E Bay are coming from China. That is why they are cheaper. Most of the LED's are made in China anyway. Your just buying direct this way instead of going through a third party that adds their own packaging and doubles or triples the price.

Many of them have poor English translations and translators. While the listings are often well written and correct, if you have to deal with an issue with them it can get to be a problem. Their time zones are 12 hours different from ours so don't expect an answer right away. It may take several messages to get them to understand. Use simple English that can be translated easily. They are usually very eager to please and resolve issues. Bad feedback on E Bay can totally destroy a sloppy vender and they have learned that. They don't want you to open a case with E Bay and they don't want you giving them bad feedback. SO they will work hard at fixing mistakes. But beware, if a seller does have a bad feedback number, don't bid on their stuff no matter how good it looks.

E Bay has a special guarantee program that E Bay will refund your money if something happens like stuff getting destroyed in the mail. But my experience has been that the Chinese company will often reship at their own expense rather than have you open a case. So be patient and work with them first.

It takes forever for stuff to get here. Mail service from China is going to take weeks. There is nothing you can do about it. You save a bunch on buying stuff from them, but you wait a while for it to get here. Sometimes there are customs delays too.

Don't plan on sending anything back. While most of the companies say they accept returns the reality is the postage to send it there will be more than the item is worth. I don't know how they can do the shipping and still make money but they have figured it out. But it is essentially a one way deal. And if they ship you the wrong item by mistake they will not usually ask you for it back. They take it as a loss.

So, to date, the majority of my dealings with Chinese companies on E Bay has been very positive. I don't hesitate to buy from them.

By the way --- I love the items that are free shipping. I ALWAYS look at shipping charges and consider that as part of the price. Some underachievers try to make money on the shipping and will disguise an items real cost and add unreasonable shipping charges. I saw an item recently, a laser pointer, that said it would ship first class mail and would cost $25.00 for shipping. When was the last time you sent a letter that was under a pound and paid $25.00 for the stamp? E Bay has a policy against unreasonable shipping charges. They view it as a way to try and get around the sale fees. Yet people still try and do it. So always consider shipping charges when you bid/buy an item.

Step 4: Buying in Bulk

Picture of Buying in Bulk

Sometimes the best price breaks are from buying in quantity, but not always.

With LED strips you literally need to do the math. Always figure it out to the cost of a 20 module strip since that is the way the are almost all sold.

For example one strip might have a price of $8.00 while another company will sell the same thing only they are offering 100 modules for $50.00 of the same thing. Well 100 modules is 5 strips of 20. Five strips for $50. is $10.00 a strip so they are $2 more per strip than the other one. Always do the math.

The LED's that I used were ones I bought in a bulk pack, buy it now deal. The are similar to this :

The ones I bought were a little cheaper than this, but notice the free shipping. They will send you a large box with 30 LED strips (3 of the packages in the picture) all the way from China and do it for no charge. Not to bad.

600 modules is 30 strips. Thirty strips for $212. comes out to be close to $6.90 each.

Now when you do an EBay search for similar items (it's one of the options in the category view) you find this :

Right away this item shows up

So that is one strip for $10.00. A little more than the price of the 600 but if you only need to buy one---. Might not be a bad deal. But how about this, you buy the 600, keep the ones you need and sell the rest to your friends for $10 each and make a small profit.

How adventurous are you feeling?

Here is another one:

That is for 1000 and $329.00 Doing the math it comes out to be $6.60 each strip. Not that great a deal except these are warm white which tend to cost a little more. Still only 30 cents less is not a huge amount.

Continue through the search and you find this one:

That's $8.55 with free shipping and you can buy as many as you want (says 9 available) . That is not a bad deal. Might be what your looking for. Ok, you get the idea, then you run across this one:

Notice it's a 6 LED unit and it costs less than the 5 LED one that you just looked at.

Actually these (the 6 LED) have dropped in price a lot lately. They used to be over 10 each and no one had them in bulk. Well they are still not in bulk but the price is now equal to the 5 LED unit. Maybe I should pick up a few of them.

So there are a lot of choices but by smart shopping you should be able to get a reasonable deal.

Step 5: Some RGB

Picture of Some RGB

This is a search for some RGB modules.

This search has a lot of other stuff with it. So it's a bit more confusing.

I think the average range for a 20 strip RGB is in the $10 range. Anything under 8 I would consider to be a good price now.

There are also a lot of single color strings. You can get all green, or blue or whatever.

Step 6: Power and Control

Picture of Power and Control

To power the string you need a power adapter. You can use any 12 volt adapter if it can provide enough amperage to power the string. You can get all kinds of connectors on E Bay that allow you to connect the power to the string. RGB strings use 4 wire connectors.If you are hooking up multiple strings and need a heavy duty power supple you can find those on E Bay also.

To turn the string on and off and control the brightness you need a controller. For single color ones there are simple in line switches. Some of the better controllers work on RF with little remotes. Interestingly I discovered that most of them operate on the same frequency so one remote can control multiple switches.

The little in line units have a limited power capacity. You can burn them out if you go past what they are rated for. Bigger unites that can handle more power are not as mobile. There are lots of choices available with new designs showing up all the time.

For the RGB units you need a special controller. The most common one is an infrared one with 2 different key size remotes. They work. But a way better one that I tried is the touch sensitive remote that is RF. I really like the unit. Below are a few searches for different controllers.

Step 7: Defective Stuff

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A few rare times I have received what I would call seconds. Items that still worked but had things wrong with them. Like the picture shows, a few modules had some melting on them and the resin coat seal was messed up. It has been a very rare thing, but like in any thing you always take a risk. If it's really bad then let the company know and if necessary file a complaint. If it not a big deal make note of the company name and either don't buy from them again or buy with caution.

All in all I have found shopping on E Bay is safe and allows you to get interesting products that you can't get elsewhere. But use caution with it just like you would with anything else.

Step 8: Wire LED's

Picture of Wire LED's

This is just something I came across that I thought someone might be interested in seeing.

They have been making wire with tiny LED's in it. The wire is coated with a clear insulation. They are also on E Bay.

A search result for those if anyone is interested.


nathanaloysiusbash (author)2015-07-18

I have been trying to figure out the led ebay thing for a while now. I've widdled it down to buying just the led chips and not even led specifically marketed drivers, just random raw dc power supply circuit boards. My electronics skills are low. I havent actually built a fixture yet. I have figured out that the square 10 watt leds chips clip on to a 9 volt battery to make an instant flashlight. The way the vendors from china can make money after paying shipping is that they dont pay shipping. Shipping is free for them and thats why its free for you. Its a trade agreement between the usps and certain chinese vendors to encourage trade. Different vendors have different shipping deals. Theres standard international shipping for a couple dollars which doesnt take too long. Theres epacket for a couple dollars which is about 2 weeks. Then theres the world bank vendor world leader shipping rate-Priority usps mail delivered for free. Theyre all secretly in cahoots. like coke and pepsi. or mac and ibm. or god and the devil. you know...yea.


b1aflatoxin. (author)jimluschen2017-01-07

Context clues?

please tell me that your 10watt led is heatsinked or not on for very long when powered. Any LED that is high powered should be heatsinked to help the lifespan. just like any other light, they produce heat. if the heat is not disapated the chip will burn out.

No. The 9 volt flashlight? You just bend the tabs and it clips onto a 9 volt and its real bright. I dont have any at the moment. But when i tried it i left it clipped on for a minute or so to see if it would get hot and there was no noticable heating. Of the led or the battery.

papatait (author)2016-07-12

I too want to use energy saving bulbs. So, I bought some corn bulbs (110 volt screw base) I bough 36 led ones, and 56 led ones. the 56 led were very bright but I have gone through 3 already and am leery of using more. I am guessing that something in the electronics is burning out or shorting to the point that the leds will only burn dim or only a couple light in the bulb. not being an electronic educated person, but curious I looked inside of the ones that failed and t0 see only a couple of electronic pieces, so my thought is that the electronic pieces are not big enough to st5and up to the load they are subjected to.

I also purchased strip lights to replace the Christmas tree style lights on our back deck to add more light, with a transformer to drive them. They have been great and give a lot of light. This is actuly a reply to your second guide on Instructables.

dtpit (author)2016-07-03

what's wattage of each 5050 led strip with 12 volt supply

iceng (author)2015-07-30

I'm involved in designing Coast Guard PCB LED lights where the
technology changes faster then the government procurement cycle ( see
first 2 pics of 6-Red+24-Wht ) a few years ago and the brighter lower
current replacement light 7-Red+7-White SMD of last year. Oddball LED
counts are to match ever changing LED forward voltage specs and a strict
Navy operating voltage range.

The point being ... that even
CREE LEDs are going to be changing for our lifetime and it is useless to
worry about power semantics especially China LED vapor-wear.

Just buy the amount of LEDs you need, run your own tests on them and modify your design to work them as you need and want !

DustySeven7 (author)2015-07-26

I have not seen anyone mention this so i will. Be very careful and look that the specs for the RBG LEDs. There are 2 types and both use 4 wires, but are very different. There is Digital and Analogue LED strips. Digital RGB LEDs are unique from the Analogue LEDs in that every led in the strip can be controlled individually through unique code or special controller. What usually gives this away is the color of the wires used. Digital LEDs have red and black which is power, but then have 2 other wires that are typically Green and Yellow. The green is clock and yellow for data. Analogue will typically be Red,Green,Blue,Black. and there are 2 types of those. Majority are common anode, the black wire is positive voltage and the 3 color wires are the grounds for each color. The other type of analogue is common cathode where black is ground. Based on this info, the RGB LEDs shown on the first page appear to possibly be digital LEDs, if you were to send power through the green or yellow wire the unit would be destroyed. Just want to get this info out there to help.

heath.israel (author)2015-07-22

"Almost all of the LED's being sold on E Bay are coming from China. That is why they are cheaper. Most of the LED's are made in China anyway."

Careful with that statement. Many things bought directly from China have some serious shortcuts taken and you won't find them until you've used the product for awhile. Buying from China skips the entire QA process that Company's in the U.S. require. Two products can look identical but the one purchased through a U.S. Company can be far superior. For something small like an LED or LED strip, the cost probably outweighs the risk...but anything with a serious price, any type of safety product, anything you ingest or anything that touches what you ingest needs some serious thought before you buy straight from China. Think about that when you're putting whatever it is together. If dependability, durability, safety, or ease of repair is an issue, there's a price for it.

starphire (author)heath.israel2015-07-22

"Buying from China skips the entire QA process that Compan(ies) in the U.S. require." If only it were so simple as that! I fear your generalization is going to mislead some people into the very type of unhappy experience you are trying to prevent.

First, which Companies in the U.S. require a QA process on LED strips and modules? It's certainly not even close to being a universal "requirement" (some might even interpret your statement as though there was a law meant to protect them from QA evaders). There are tons of small time U.S.-based vendors (on eBay and such), small hobbyist outlets in the US and other developed countries that most certainly DO NOT have the resources or even interest in doing their own QA, or sending buyers to China to inspect the factories personally - they are simply buying from those exact same sources in China in wholesale quantities and selling smaller quantities at retail from the US or wherever.

Second, of the companies that DO care to protect their reputations and customers from poor quality goods, unless they are Really Big (i.e. multinational) companies with major buying contracts from a particular factory and a full-time onsite QA inspector at the factory, they really have no guarantee of what they are getting with each batch either. Instead, they can offer a warranty to replace your LEDs if they turn out to be defective - which is built into the higher price they charge. This is not the same thing as having that super close direct factory connection as I described above. If you know of ANY such company based in the US, in fact, please tell us!

I generally agree with the basic message that you get what you pay for, more or less. Usually. But this particular market is not a good example of that being true all the time - there are ripoffs, fly-by-night sellers, counterfeits, good guys, bad guys, but in the end the fact remains that ALL of these strips and modules with LED packages costing just a few pennies each at the factory are subject to having little or no quality control beyond a power-up test to see if it all lights up. Reliability is quite often dependent not just on how good the parts are, but in how appropriately they were used in the application. Trapping heat and overdriving them is the #1 cause of early failures in the LED world, whether the parts are of the highest quality and price or the cheapest nameless stuff you could find on deal extreme.

diy_bloke (author)2015-07-22

buying from China -if you are a bit careful what you buy- is usually a good deal.
If I buy electronics goods online ina local store here, The minimum order is 6.50 euro. at least 2.50 euro is added for shipping and another 50 cts to handle the payment.
If I shop at Dealextreme or Aliexpress, I have had e.g. an Arduino nano delivered to my door for in total 1.90 euro.
Sure it can take some time to arrive, but usually that is no problem. If I really need something the next day, I just have to order at a local webshop and if I need it today I have to go in town at an electronics shop where an attiny85 costs 7 euro's(!) and I probably pay 2 euro in gas.

karossii (author)2015-07-22

I have found that using Amazon, and/or direct sites from asia such as and, end up with far better prices. Of course, with those options you are almost guaranteed to have to buy in bulk - but if you plan to anyway, you can save a lot of money!

You do still need to do the math; at every site and even in offline catalogs, there are plenty of seemingly good deals that are not so great when you figure cost per bulb. But I've found, at least for me personally, I save half or more by avoiding ebay for bulk purchases from china.

karossii (author)karossii2015-07-22

Also of note - when shopping amazon as a prime member, you may notice a lot of them are prime eligible; free 2nd day shipping. Watch out for how soon the product actually ships, though. It might get to you within 2 days of shipping, but not shop out for a week or a month. Sometimes you actually do get 2nd day though...

schuie (author)2015-07-22

I use that exact dimmer module to control the strips I use as backlight on my TV/monitors and vinyl display lighting. For the most part, it works great, but every once in a while the power button on the remote doesn't work until I've unplugged and re-plugged in the AC adapter, (effectively "rebooting" the device, I guess). Small inconvenience, especially considering the price and functionality, so I just deal with it.

castleroc (author)2015-07-21

Thank you for the clear concise report. Future projects will bring me back here.

nathanaloysiusbash (author)2015-07-18

Anything that says reurns accepted on ebay, you will get your money back if you want to return it. Look at the chinese vendors star ratings, 10s of thousands of sales made and always near 100% average rating. They will take it as a loss, theyre just banking on people being honest and their products being as described. The whole ebay site is terribly sided on the side of the buyers. the buyers can screw over the sellers with basically no consequences to them as buyers.

Parky1972 (author)2015-07-18

A note to UK bulk buyers.

Anything bought from outside the EU is subject to VAT if over the value of £15.
Most of the Asian sellers mark their goods as 'Gift' but not all.
According to the .GOV website, items marked as GIFT are exempt from VAT until the value is £36 or more.
But exercise caution. Often it's cheaper to buy in multiples less than £15.

Royal Mail add their own charge if they feel they have to open the package to check it's VAT/Duty ratings. Which I *think* is still £8. Plus the VAT you may be payable on the item(s) themselves.

So yes.
Buying from China can often be much cheaper than 'local' buyers. I buy a lot of electronics components this way myself. Just be careful of any VAT or Duty charges.

2ndopinion (author)2015-07-18

Several weeks ago I started buying from China and I found that all the "waterproof" ones that had a silicone covering would turn brown over time which was not usable for undercounter ighting which I needed. I wonder if they have improved that yet?

3967 (author)2015-07-18

i buy since 3 years directly from china on ebay because, my local shops just buy there too and just sell it for the 10x price. So buying directly saves huge amounts of money and so the waiting time is really worth it. A good tip i have too: Test and note out the sellers delivery times(buy 2x), some sellers may be more "expensive" (~1-8%) but they use other postal services so often the delivery time is 50-75% faster (10-20days) than the standard chinese post (30-40 days). To overcome the delivery lag, i just buy 1-3 items per day so i have a constant item flow :D. You should think today what you will need/like to have the next month. :)

pEvans (author)2015-07-17

Thanks, helpful article. Do you have a name or part number for the item on the last page (clear wire with embedded LEDs)? Thanks.

Vyger (author)pEvans2015-07-18

They come in many colors, lengths and some are battery powered and some adapter powered. This is a search showing some. You might want to do more searching.

Jean0x7BE (author)2015-07-14

Cool instructable, thanks! Do you have any experience with the 5630 leds? I've gone mostly with 5050 until now, but ordered a few 5630 strips, seems like a bright and nice light.

steven4872 (author)Jean0x7BE2015-07-14

The numbers 5630, 5050,5630 refer to the type of plastic case that encloses and protects the actual LED. they are not part numbers and These numbers don't tell you anything about light output , color or manufacture.

gadgeteer123 (author)steven48722015-07-17

Please do a little more homework before publicly posting comments. The numbers refer to the size of the actual SM diode in tenths of a millimeter. A 5050 diode thus measures 5.0 mm x 5.0 mm. Most diodes are standardized to within a specific range on light output, color, and power draw. By looking at your use of the English language, I am suspicious that you might be a Chinese manufacturer. Pun intended. Not meant as a jab, but many people are learning from the article as well as the comments.

steven4872 (author)gadgeteer1232015-07-17

"I am suspicious that you might be a Chinese manufacturer. Pun intended. Not meant as a jab, but many people are learning from the article as well as the comments."

No i live in California and work in the semiconductor industry and have an electronics degree.

An LED by itself is a semiconductor crystal commonly refered to as a die or chip. You can buy unpackaged LED die from cree and they are smaller than 1mmX1mm. Here is a spec sheet for it:

Obviously this is too small to handle and they are surprisingly easy to damage. As a result the die is often attached to a plastic case and coated with epoxy to pretect it.. This link shows a drawing of a case with the die mounted in it:

Yes LED are often sold in standard colors 2200K, 2700K,3000K 5600K. However that does not mean all manufacutres us the same phosphors . If you then measure the spectrum of LEDs you will find a wide variation from manufacture to manufacture.

One item in spec sheets is CRI or color rendering index:

CRI is related to the spectrum output of the LED. low cost LEDs might have a very low CRI value. Commercially available LED bulbs typically have a CRI value of 80 or higher. High CRI LED's cost more than low CRI LED's. For many projects low CRI may not be important but for other projects (grow lamps for example) CRI may be more important the color temperature.

the problem I am trying to explain is that the speck sheets from vendors on Ebay and even typically are very incomplete and instead of listing precise number often list a wide range. That is why Vyger had power measurements that didn't match calculations he made from the manufacture specs. If he had used parts with complete spec sheets his measured power consumption numbers would have been much closer to what is listed on the spec sheet.

ac-dc (author)steven48722015-07-17

They do give you a reasonable indication of brightness for a particular color, at a specific point in time since even the generics get a little brighter year after year. In other words making all other variables as equal as possible...

Driven at the same % of total power rating, 5630 are a little over twice the lumens of 5050. Not coincidentally, they also need a little over twice the drive current to do so, so in the end if you have decent thermal management they just allow a higher brightness per area of the LED array. If you don't want to put any thought into thermal management then the lower power density of 5050 will be more forgiving by forcing a larger area for heat radiation.

Jean0x7BE (author)steven48722015-07-15

Take a look at this site,

steven4872 (author)Jean0x7BE2015-07-15

that is a very general discussion of some of the differences. it is not a spec sheet The case is the white plastic with with metal contacts in the picture on the web site. The led itself is a small 1mmX1mm crystal in side the case which is then covered by phosphor (theytelllow top of the cases in the pictures). The case and phosphor are made by separate manufactures and are sold to the LED manufactures which put it all together. The color, voltage, CRI andbrightnes will very depending on the phosphor mix, and LED used by the manufacture. And each manfacutre will be a little different.

Bellow is spec sheet of one manufacture of 5630 LEDs. Take a look at it it is very different from what is shown at the link you provided.

In general all three case styles need to be mounted on a circuit board with the appropriate driver circuitry and if necessary cooling. to work. If you are casing about color and brightness that will depend on the manufacture you sellect.

hvweezel (author)2015-07-17

I do have very good results with :

steven4872 (author)2015-07-14

"There is something strange going on with the power requirements. The manufacturer often gives a number of watts for each individual LED. But in experimenting with them the numbers don't add up right. Now I have been seeing disclaimers from the sellers that the manufacturers numbers don't add up and that you can't rely on the wattage being what they say. So no body appears to really understand just what the ratings are."

The reason power requirement don't appear right is because you are buying through Ebay or Craigs list. You don't know the company or even if you are getting scraps from a factory. Some of the items are sold by mom and pop shops in china. They don't know what they are buyiing, don't know english, and don't understand specifications.

For example I have Seen UV LEDs advertized with output wavelength of 430nm. 430nmis not UV, it is Violet light. I have purchased LEDs with a colortemperature of 2200K and gotten LEDs with a color temperature closer to 3000K.

If you want quality parts with accurate specifications for power, color temperature, wavelength, and CRI , buy your parts from the companys many manufactures use such as www.digikey,com or Whey you buy from these companies you now all the specs, who made them. If you buy from these sites you get exacly what is listed on the specs and many of the issues you talk about don't happpen.

Vyger (author)steven48722015-07-15

You might enjoy this discussion we had about this topic a few months ago.

Please note at least one of the people involved in the discussion is an electrical engineer.

ac-dc (author)Vyger2015-07-17

The topic is much easier than you made it out to be.

A 5 LED strip like that has a resistor in series with each LED. The forward voltage of each LED is about 3.1Vf.

With a 120 ohm resistor in series and a 12V supply the resultant current flow is about 80mA per LED, 0.25W per LED.

When you drop the supply voltage to say 10V, because it's a resistor limiting current, the math changes. The forward voltage might drop from 3.1 to 3.0, and the current to 60mA, so now instead of 0.25W per LED it's 0.180W per LED.

My 3.1Vf estimation above might be a little off, perhaps by as much as 0.2V but the change with input voltage is relatively the same.

PS - Typical 4' T8 fluorescent tubes now use 32w each instead of 40W each. There is no possible way to use generic LEDs at this point in time and have a higher lumen/watt output than the average 4' T8 fluorescent tube driven by a remotely modern high frequency ballast and that's with the best of circuit designs including a high quality (efficiency) current regulated supply instead of a large loss in a current limiting series resistor.

If you want to significantly beat the efficiency of the typical 4' T8 fluorescent tubes, start with an efficient current regulating PSU and major brand, higher wattage and higher efficiency LEDs, for example those from Cree, Philips, Osram, etc., not Epistar or an even less well known name.

ac-dc (author)ac-dc2015-07-17

Additionally if you want accurate measurements, start out with a power supply capable of more rather than less than the rating of the LED product. It could be producing a ton of ripple and your meter isn't reading it correctly (perhaps additional capacitance on its output would improve meter reading accuracy, but that is an extra inrush current and strain for an already overloaded PSU that won't have good lifespan itself so basically, take a PSU's rating seriously and don't overload it then wonder why things aren't adding up.

ac-dc (author)steven48722015-07-17

You are right but you are ignoring one of the most important parameters when people are just after a lot of cool white light: PRICE.

Digikey and Mouser charge a truly obscene amount for decent LEDs in small quantities (less than 1000 or more). Literally it would cost over $100 for the same amount of light from products like the one the author linked for $8, if buying the low(ish) current LEDs instead of 1W+ per LED.

The true, conservative (long life) ratings depend primarily on the package type, quality control (mitigating infant mortality by derating current and using a higher # of cheaper LEDs which also eases thermal management), and of course heatsinking but we'd be talking apples:apples comparison using same heatsinking.

So for example Philips might rate a SMD 5630's lumens at 100mA and at 25C thermal junction temperature, but state the max current is 150mA, while the generic may just state max current is 150mA or just current is 150mA then give a lumen rating for that instead, leading people to believe it should be ran like that and would give the lumens at the higher actual junction temperature.

CraigRJess (author)steven48722015-07-14

Cool, thanks.

tucker135 (author)2015-07-17

Good posting. I like your comment regarding shipping charges. This is the main reason my EBay to Amazon purchases run 99% EBay. Comparatively speaking, EBay rocks.

john.averick.1 (author)2015-07-17

I love this tutorial on LED lighting and buying such. Getting older now I need more lighting around me in certain areas and this tutorial is the key. Than kyou

ac-dc (author)john.averick.12015-07-17

This is not really the thing to do for broad area lighting, now that major manufacturer LED bulbs have dropped so much in price. By the time you buy the controller and power supply, plus addt'l materials and the time to build your enclosure, you might as well have bought some ~ 700-850 lumen LED bulbs that work in existing E26 base fixtures AND the typical 10W 850 lumen bulb is about 75% brighter and/or more efficient.

Generic Chinese 5050 LEDs are far less efficient than higher wattage major brand US or European LEDs, but to get the latter two at good prices you take advantage of them being integrated into major brand light bulbs already.

john.averick.1 (author)2015-07-17

I really feel informed now about buying and using LED lighting. And He's right. I've had mainly good experiences dealing straight from China. They usually send me another item free of charge and I don't even have to return the malfunctioning item.

oldfatnbroke (author)2015-07-17

I've got several projects in mind that need LEDs, I'm strictly a newb when it comes to working with them, I have been hesitant about buying them from China on ebay. This tutorial gives me some courage to make the plunge. Thank you!

richg99 (author)2015-07-17

Well done explanation. I will keep this for future reference.

bmaverick (author)2015-07-17

Other than buying LEDs in modules, have you looked at spools/reels of the 5050 series. Sure, you must cut them at specific places and wire connect them, but the cost is much less than $6.60 a module. Sure, the spool/reel type are mainly single color, but for certain projects those are ideal.

Your write-up is very handy. Good work on a job well done. This will help many people.

Shanem21 (author)2015-07-17

Well done...

mrthrifty (author)2015-07-17

Informative, skilfully structured, well written, generously illustrated.

Many thanks!

suskojm (author)2015-07-16

This was a very instructive article. It has help me decide to try this out.

thanks for the info. Have a great day

Monsterguy (author)2015-07-14

For the last few years eBay has been taking a cut of the mailing charge exactly as they do for the sale price.

CraigRJess (author)2015-07-14

Nice work!

Two Paddles Design (author)2015-07-14

Thank you so much for this! I've been shopping this way for awhile but have not been able to put it all into words, I will be linking back to this with some of my other projects.

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Bio: The name comes from the First Star Trek movie, that pretty much says it all.
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