bigclive Posted October 30, 2014 Share Posted October 30, 2014 I recently got some 20W LED floodlights for my workbench to provide even white lights for work and filming teardowns. So before installing them I took a look inside first. The video says it all..... https://www.youtube.com/watch?v=_Kd49T0ZxNU Link to comment Share on other sites More sharing options...
DrV Posted October 30, 2014 Share Posted October 30, 2014 Nah Clive. That's 20W Music Power:-)Dave Link to comment Share on other sites More sharing options...
bigclive Posted October 31, 2014 Author Share Posted October 31, 2014 PPP Peak Photon power. <_< Of course, I immediately ordered a pile of random versions from different suppliers to take to bits too. Link to comment Share on other sites More sharing options...
sleah Posted October 31, 2014 Share Posted October 31, 2014 I just bought a selection of BC fitting LED 'bulbs' from AliExpress. Complete rip-off even for the extremely low price.A 10W that's about half the brightness of a B&Q (Diall branded) 9W that I have and wait for it..... it draws about 20W!!! WTF!! I'll do a tear down video sometime. No driver AT ALL, just a capacitor and some SM components that could be resitors or diodes - will have to check with the magnifier. Great for lighting a cupboard, but apart from that, complete junk. Link to comment Share on other sites More sharing options...
gyro_gearloose Posted October 31, 2014 Share Posted October 31, 2014 You may be able to salvage the LEDs if the you don't mind a bit of work adapting them. We've got some GU10 LED lamps that have either started flickering or stopped working altogether. I pulled one apart to see how they worked and found that the driver electronics were burnt out. I hooked the LED directly to a couple of batteries and got a decent amount of light out of it, far more than when it was mains-driven :) Link to comment Share on other sites More sharing options...
timsabre Posted October 31, 2014 Share Posted October 31, 2014 No driver AT ALL, just a capacitor and some SM components that could be resitors or diodes - will have to check with the magnifier. This is not necessarily bad, some LEDs are designed for mains drive (basically lots of LED dies in series to make the forward voltage about 200V). A "proper" brand is the Acriche from Seoul Semiconductor but no doubt there are plenty of clones of it. Link to comment Share on other sites More sharing options...
KevinE Posted October 31, 2014 Share Posted October 31, 2014 unless safety and quality law is actually enforced, it will always be 'buyer beware'. Clive did you test the filter leakage to case on the unearthed fittings? Link to comment Share on other sites More sharing options...
bigclive Posted November 2, 2014 Author Share Posted November 2, 2014 Filter? I'm not surer you'll find much more than the cheapest most minimalist choke on the input of these things if even that. Although the casing of the current limited driver is aluminium extrusion, the internal PCB is potted in rubber goop and just has live and neutral going in one side and positive and negative coming out the other. Theoretically it could almost be classed as double insulated if there was serious input to output isolation, but I very much doubt there is. The LED itself has an unknown breakdown voltage between the chips and the aluminium plate they are mounted on. Part of me wonders if the reason for the conveniently neglected earth is to avoid damage caused by high voltage insulation tests, although if there's a path potential between the mains input and the case then it's already a failure. And the fact the case is aluminium on an outdoor fixture pretty much demands an earth bond test anyway. A 10W that's about half the brightness of a B&Q (Diall branded) 9W that I have and wait for it..... it draws about 20W!!! I'll do a tear down video sometime. No driver AT ALL, just a capacitor and some SM components that could be resitors or diodes - will have to check with the magnifier. Capacitive droppers are quite common in the low power lamps. My favourite little 2W GU10 lamp from Philips uses a capacitive dropper. How did you come up with the 20W figure? The capacitive droppers do not have a good power factor so the measured current is not multiplied by the mains voltage to get the total power. You have to multiply the measured current by the combined forward voltage drop to get the real LED power dissipation. I'll bet your seemingly 20W lamp does not actually get very hot. Oh, and completely ignore any power ratings quoted by Chinese suppliers. They just make them up. If you look at my other video's on YouTube you'll see lots of LED lamps being disassembled and analysed. Link to comment Share on other sites More sharing options...
marktownend Posted November 10, 2014 Share Posted November 10, 2014 I'd ordered a single '10w' flood of this style from a random ebay seller as a trial unit, by chance on the same day that you originally posted so I was quite intrigued to see your video. However, the earthing on my unit consisted of even less than yours - the earth wire had just been cut at the point it came out the flex inside the unit. I've not got anything to measure the output with, but I was happy enough, nothing outstanding but not too feeble either. Absolutely no markings internally to give any indication as to what it actually might be. Shame about the earthing (and the fact that the flex is so short) as they'd be useful little lights if they didn't need modifying to make safe to use and I suspect they'd need a fresh dose of goop to maintain the IP rating after taking them apart. Link to comment Share on other sites More sharing options...
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