DC 12V 5M 300LEDs Not Waterproof Single Color RGB LED Strip 5050 SMD 5630 3528 Flexible Light Neon Lamp Tiras LED Light Garland (WHL #7)
…also known as
NEW DC 12V Not Waterproof 5050 5630 3528 Single Color RGB LED Strip 5M 300LEDs Flexible Light Neon Lamp Tiras LED Light Garland
DC 12V 300LED 5M LED Strip 5050 RGB 5630 3528 3014 Not Waterproof LED Strip Light Flexible Neon Lamp Tiras LED Light Tape Stripe
5m/roll SMD 5630 DC 12V Not Waterproof LED Strip White / Warm White String Lights Fita Lamps for Home Lighting Cabinet Decorate
Well, you get the idea. It’s LED strips this time, and I chose 5630 size in warm white color. I’ve been ordering quite an amount of these, and in hindsight, I would rather buy A LOT of them instead of getting 1-2 reels at a time. But first things first: I bought them from AliExpress for 3.06 € to ~ 2.70€ a reel (5m per reel) from January 2016 to May 2016 from two different sellers. All of them were shipped in nice big anti-static bags, not very much cushioned, but all arrived in good condition. One reel was cracked, but I guess you won’t use 5m reels of uncut LED strips for loading a pick and place machine, so that shouldn’t be an issue.
Why 5630? Well, the bigger case in comparison to 3014 or the very common 3528 LED types should make for a better heat distribution and also the larger area of the converter material (blue to white) makes the individual LEDs less of a point source. This also holds true for the 5050 SMD format, but these are the most expensive. 5630 is somewhat cheaper, so I chose them over the other types.
Now, how do they look like? Exactly like this:
Notice anything? Both come from the same seller (Shenzhen better fly Technology Co., Ltd., to put a name on it) from the very same offer on Ali.
Yes. Bastards. These LED strips are not unipolar ones with a bridge rectifier in it or something fancy. These are two physically different units and one has the LEDs upside down. Moreover, the resistor is different (100 vs. 120 Ohm per group of three) and also the flex strip is different (the seller told me), including a different type of sticky tape on the back. The very first unit I received had some fake 3M tape, while the others do not show any name, brand, type. Well, I still wonder why they bother putting 3M on it, when 4M obviously is much better… (I don’t like the real 3M for different reasons, but that’s just me) Everything else is no-name, a classic Wan Hung Lo product – sold under the same name, totally different product inside.
Anyway, I’m massively pissed to get different units when buying the exact same item again, and I had a month-long dispute with the seller, including a cancelled order and some small refund outside of the Ali payment system. It’s not so much about the money (remember: 3€ per 5m), but rather not being able to buy additional strips when needed, as they have different construction. So when building my light box, I now have marked all 36 individual strips with an GND indicator, in order to connect them all the right way. It’s hard to get it on camera, but because of the different load balancing resistor, brightness and also colour are not quite the same between the strips. And that’s pretty shitty.
But physically different strips is not the only issue I had. The units were advertised as “3.84 W/m”, so I expect something short of 20 Watts per reel. Turns out…nope, only in highly paralleled configurations. The flimsy metal deposit on the plastic strips has way too high resistance to carry enough current to light up more than 2-3 meters at a time. 5m connected at both ends juuust works, but anything longer than that will have much lower performance (in total) and also lower brightness towards the middle of the strip.
When I cut the strips for the light box, I measured them while cutting and also added them back together for a second reading. I measured current with both my Uni-T UT203 clamp meter and an volt/amp meter that I will be featured in another post. Voltage was spot-on 12.0V as supplied by an old Enermax ATX power supply, also measured via the voltmeter under test, my main Peaktech 2010DMM and the voltage meter directly connected to the ATX supply. Here’s the graph for snipping (or adding, I avg’d the reading) 60cm pieces = 12 groups / 36 LEDs, supply only at one end of the strip:
Uni-T is always in lighter shade, notice the two Y-axis with wattage per meter (remember: “3.84W/m”) on the left and total wattage of all elements combined on the right.
While I’m happy with the amp meter/UT203 performance, the graph clearly shows the problem with longer strips: Massive loss of wattage and therefore light output. So I have to wire up all 3×12 strips for the light box in parallel, which is quite an effort compared to just having them in series and adding one wire on each turn. Otherwise, I’m far off the 20 W/reel figure and I’d almost need two reels to reach that.
One more thing: Reviewing this LED strip finally forced me to put my hand spectrometer together, or rather, to build the second unit that can get modified to fit the camera without scrapping my existing one. Took me two hours, but I’m glad I finally did it.
Here’s some calibration shots with a red (“650nm”) and blue (405 nm) laser pointers:
both are off around 12-ish nanometers (reading too low, needs adjustment) – I tried adding a shot from my sub-400nm UV LED flashlight, but this is basically impossible due to fluorescent paper ingredients. Even the lasers are tricky because they are such powerful point sources, see the additional reflections aside the glowing narrow stripe at the main wavelength.
As you can see, all LEDs lack the band between blue and green, and only the Cree LED has “something” around the narrow yellow band. So these 5630 LEDs aren’t great, but they are not horrible either.
I think that’s all I wanted to share, so let me make a short conclusion: At around 3€ per 5 meters, these LED strips are hard to avoid for general lighting purposes. At their low wattage it is possible to operate them without heat sinks (aluminium profiles are darn expensive..), yet I wouldn’t trust the sticky tape on the back very much – use additional spray glue if you really want them to stick down. With the balancing resistors the individual LED groups light up very evenly, yet if you go down much below the 12V rated voltage (8V or less), single ones might pop out a little. Light spectrum is okay-ish, nothing to worry, but also nothing to write home about. Use additional stranded wire for powering longer strips (above 2m), as the internal power traces cannot support high currents. And most important of all: Buy once, make often. Don’t buy small quantities and re-order, you probably will get different LED strips that will mess up your projects.
Why? Because in Wan Hung Lo land, saving one-and-a-half cents per unit because of even cheaper plastics and LEDs will change entire production plants to use that junk.
Oh well, more goodness to come.