A look inside 2 GLW “50 Watt” LED Flood Lights

I bought a couple GLW led flood lights from Amazon – a “grow” one and a warm white one. You’ve probably already seen dozens of them on eBay, but they look something like this:

GLW 50W Flood LIghts

These are both 50W units. Here, the one on the left (black) happens to be the “hydroponic” one, and the one on the right (grey) is the “warm white” one. You can usually find whatever color LED you want in the black (or grey) case though.

The short version is that they’re very cheaply made, but I’ll go into details below. I’ll start with the hydroponic/grow version on the left, and then cover the warm white on the right.

Inside the (black) 50W hydroponic edition

4 screws and the bezel comes off. It’s flimsy, so if you remove (and reattach) it be careful to maintain even screw pressure all the way around or it’ll flex, corners will kink, and it won’t end up flush with the glass.

With the bezel off, the glass pulls out. Rather than drill holes through the glass for the screws, they broke off the corners. Incidentally, this is why tightening the screws can lead to kinks – the bezel corners just bend into the space where the glass corners used to be. Anyway, it’s not a very “clean” break, so a couple glass shards may come out with it (they did for me). The glass itself is surprisingly thick, so I wouldn’t be overly concerned about it breaking too easily.

With the glass out, we get this:

GLW Hydroponic 50W with the glass removed

Few notes at this point:

  • The ground wire isn’t connected to anything. If a live wire shorts to the case, the case will become live without tripping a breaker (in other words, this device is a bit of an electrocution hazard). Do yourself a favor and only plug this thing into a GFCI if you’re outdoors, near water, or anywhere near a ground.
  • Only 2 screws are holding on the reflector. They must be operating on razor-thin margins if they can’t afford to install all 4 screws.
  • The cord you see attached actually *did* come with this one. Full cord with a 3-prong outlet. This isn’t very common, so if you’re shopping for one, make sure you find out before buying if you aren’t hard-wiring it.

The reflector itself is really delicate. Not as flimsy as aluminum foil, but more flimsy than the aluminum foil baking dishes you can get at the supermarket. 2 screws and it came off to reveal….

GLW Hydroponic Flood Light - 50W LED

More missing screws! China must be in the midst of a screw shortage. Actually, 2 had been installed, but they stripped one of them and it was rolling around loose.

As for the LED:

  • It uses 10 blue chips and 40 red chips. It is indeed a “50W” chip.
  • They actually did use a decent amount of thermal paste.
  • The surface behind it is as poor/rough as everything you see around it. So it’s pretty reliant on that thermal paste to keep cool.

I ended up removing the LED, sanding the surface flat, drilling out new holes, and reinstalling with 4 screws.

On to the driver:

GLW Hydroponic 50W Flood Light - the driver

It’s actually a 30W driver. You can click the image for a larger version, and you’ll see “1500mA”, but in reality this one put out 1090mA. It’s also smaller than every other 1500mA off-the-shelf chinese driver (actually, it’s exactly the same size as all the 30W 900-1050mA ones).

This was the first part that really bugged me. Okay, you’re using a 30W driver in a device advertised as 50W. Fine. There are legitimate reasons to under drive LEDS (heat and longevity). But to go out of your way to intentionally mislabel the driver just seems shady. I know, I know… I should probably be more concerned that the device arrived as an electrocution hazard and had a loose screw rolling around, but for some reason this bit just really irked me more than the rest.

The Actual Specs and technical bits (for those interested):

  • 25 Watts Power draw (50W led with a 30W driver)
  • 23 Volts
  • 1090mA
  • Pretty low power factor (about 0.63)
  • 40˚C on the case behind the LED after 1 minute runtime (20˚C ambient)
  • 50˚C on the case behind the LED after 5 minutes runtime (20˚C ambient)
  • Thermal conductivity of the case is pretty low. Edges of the case were still at ambient after 5 minutes (with no airflow). It’s clearly not “true” aluminum but it some sort of cheap aluminum alloy.
  • If you wanted to replace the driver at some point, you have just over 170x60x40mm of space to work with. However, there are a couple 6mm “nubs” that may get in the way if you exhaust all the space (so just under 40mm high if you use a wide driver).

Final pics:

GLW Hydroponic 50W Flood Light turned on GLW Hydroponic 50W Flood Light turned on (camera flash on)

Most of the pics have the camera flash on, but I turned it off for the picture on the left. This thing is actually pretty bright.

I’ll get to the conclusion later, since the next one has a lot of similarities…

Inside the (grey) 50W “warm white” edition

The biggest difference when it comes to disassembly is that the driver on the “grey” one is housed in it’s own separate compartment. Aside from that, much was the same as the above:

  • Glass with 4 corners broken off instead of drill holes for screws. Flimsy bezel.
  • Same missing screws (2 installed instead of 4 on both reflector and LED).
  • Same unattached ground wire.
  • Same uneven surface that the LED was attached to.
  • The LED is a 50W COB.
  • Same 30W driver with a 50W label on it.

A few pics:

GLW Warm White 50W LED COB GLW Warm White 50W LED COB powered on GLW Warm White 30W driver

Some notes on this one:

  • I bench tested the LED at low currents. They all lit evenly and uniformly, which was a plus (these 50W and 100W LEDs are notorious for defects).
  • The aluminum behind the LED was *really* uneven, as though it had been warped.
  • In the 3rd picture, I was in the midst of swapping out the partial cord for a complete power cable, which is why the strain relief on the power cord is disassembled. The strain relief was indeed there originally, and was secured/tightened well.
  • The silicon gasket behind the glass wasn’t in it’s groove completely and was pinched in such a way that it might have been susceptible to water leakage.

This one was running at 34W (31 volts, 1090mA) which is roughly what you’d expect from a common 30W/1050mA driver. Side-note: if the LED itself were actually a 30W white LED, to keep from overdriving it, you’d often use a 30W/900mA driver to get about 27W.

Temperature of this one hit about 54˚C after a 5 minute run. A few degrees higher than the other model. Few potential reasons for this:

  • The LED COB does pull more 9W more despite using the same driver (due to the higher voltage that white LEDs use compared to reds). That’s a 30% increase.
  • The separate compartment for the driver “blocks” the rear fins of the main compartment somewhat.
  • Black is more emissive than grey and will expel the heat better. Side-note: of course, if the sun were beating on it, you probably wouldn’t want black because it also absorbs heat better.

Final Thoughts / Conclusion

If you’re a DIYer, these are actually pretty decent:

  • The LEDs themselves were good. Also easily swappable if you wanted to put in another one with similar mount locations.
  • The “aluminum” drills really easily.
  • There’s room between the small rear fins for some low-profile component heatsinks if you’re looking at upgrading the cooling capacity.
  • There’s a lot of space for an upgraded driver.
  • If you connect the ground, are fine with the heat, don’t care about the low power factor (most of us don’t), either don’t mind the driver / will replace it, and do a little work to ensure it really *is* waterproof, you’ve got a pretty solid maintainable light that can be tweaked and modded.

Not having a 50W driver is a bit of a bummer (since you’re looking at picking one up if you really wanted ~50W power output), though to be fair, I don’t think the enclosures would handle the heat since it isn’t “real” aluminum. That’s no excuse for mislabeling the drivers, but at least they’re honest about the LEDS themselves.

If you’re not a DIYer, these are probably a risky buy. Even though it’s only running a 30W driver, the temps do get pretty warm – something might go “pop” on a hot day without upgraded cooling. Disconnected ground means it’s less safe, there’s a chance of loose screws inside, it’s debatable how water resistant it is, and with that 30W driver it’s not really putting out the light you’d expect in a 50W unit.

I’ll leave it there. If you’ve picked up any of these units and have some thoughts (good or bad), feel free to leave them below!

  • Anonymous

    Been enjoying reading here, getting ready for my first DIY led fixture.

    I noticed on amazon this 10w version of the LED ‘Flood’ light:

    Below I noticed what is frequently bought with it:

    Wonder if those two become this:


  • Georg

    Disconnected ground, metal case, lose screws etc…sounds like a “Liveleak” video in the making.
    They wouldn’t even be allowed to be sold/imported in some countries, like the EU. You are correct, until you are a DIYer and can “fix” those lights before you even use them, I’d consider them very risky, if not potentially fatal….
    (By the way, coming all-the-time back to your great CXB3590 page with the efficiency data, good job!)