Here is a list of all the postings Michael Kerton has made in our forums. Click on a thread name to jump to the thread.
Thread: LED GLS bulbs |
06/07/2020 09:37:09 |
Posted by Oven Man on 05/07/2020 10:13:27:
Posted by Michael Gilligan on 05/07/2020 08:27:49:
Posted by Ady1 on 05/07/2020 08:01:51:
So is that the startup surge killing the driver? and is it the power supply or the led that fails?
. No ... The driver seems to survive, but I think the bad switch contacts are acting as a diode for a few mains-cyles: de-stabilising the driver and over-driving the LEDs. To quote my previous post: ... a recent failure resulted in two visibly burnt LEDs in the array [one of which went open-circuit]. For the avoidance of doubt; that’s two LED chips in the array within a single ‘mains light bulb’ MichaelG. Edited By Michael Gilligan on 05/07/2020 08:31:12 My experience has been almost the exact opposite, the driver fails not the LED. Being the nerd that I am I usually pull failed items apart to see why they have failed. I have a collection of LED chips that work OK, just need to find a use for them. Some of them are series connected and need quite a few volts to drive them. About 20 years ago I replaced the filament lamp in our door bell push with an LED and it has worked perfectly ever since, still as bright as the day it was installed. As with a lot of consumer products the components are pushed right up to their design limits so it's probably not surprising that we see so many failures. Cost also dictates that high temperature rated components are a nono. As I mentioned in a previous thread it appears that manufactures guarantee the LED for x years but not the complete bulb. Has anyone tried getting them replaced under guarantee? Peter I had some Screwfix LED failures. The catalogue advertising blurb claimed if I recall, 30,000 hours, but they failed within six months. Manager refused to replace them as they only replace duff items withing 30 days. I complained to HQ and pointed out the consumer rights legislation. These lamps were not as described E.G 30,000 hours and were not fit for purpose As for inrush current destroying the electronics, I like to shove a thermister in series. It just takes out the hard knock on switch on.
Regards
Michael
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Thread: Cleaning an old lathe |
05/07/2020 10:50:45 |
Hi,
I found Lotoxane (Arrow Chemicals) to be really effective and it doesnt stink. |
Thread: Stroboscopic effect |
05/07/2020 09:16:23 |
Hi, Modern fluorescent fittings with high frequency instant start control gear usually operate at about 30kHZ so are well suited for illuminating over lathes. And, now most people consider LED to be the new kid on the block, old style fluorescents are really cheap. Look for fittings that have T5 lamps (thats the skinny lamps). Also, reputable manufacturers claim up to 50,000 hours lamp life. And new style fluorescents are really efficient. As mentioned previously in this post, LEDs are not necessarily robust. Heat is the main killer and quite often the difference between a high end LED fitting and a cheaper one is heat management.
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