| tabbypurr@gmail.com: May 29 03:04PM -0700 > Is GB really that far behind the rest of the world? Or is it just you? > Peter Wieck > Melrose Park, PA I'm just letting you know what's in the shops. Really I don't know what your problem is. And am not interested. NT |
| Jeff Liebermann <jeffl@cruzio.com>: May 29 08:36PM -0700 On Wed, 29 May 2019 05:57:33 -0700 (PDT), Tim R <timothy42b@aol.com> wrote: >Any heat source generates convection air flow, as long as the fixture isn't enclosed. Yeah, that's a problem with all lighting. Most fixtures (luminaires) are enclosed. Here's an example of a melted MR16 5watt 12v LED lamp: <http://www.learnbydestroying.com/jeffl/pics/LED/MR16-LED-melted-01.jpg> The lamp is the upper right is the way the lamp looked when new. The wrinkled looking lamps are what happened when they were run in a badly ventilated light fixture. Notice how much the plastic has shrunk when over-heated. The PCB in the lower left is the back of a 60 LED array and consists of 10ea 82ohm(?) resistors and a diode bridge. I haven't bothered to decode how the LEDs are wired. <http://www.learnbydestroying.com/jeffl/pics/LED/MR16-LED-melted-02.jpg> The LED front view is in the upper right. The lamp in the upper left in an MR16 incandescent light. It's made of an aluminized glass reflector, aluminum frame, and ceramic base. I think it's rated at 20 watts. All were mounted with the base facing upwards. I couldn't find the original listing, but I think it's the 60 LED (5 watts) version of this light: <https://www.ebay.com/itm/GU10-MR16-E26-E27-LED-Spotlight-Bulb-2835-SMD-4W-5W-6W-Lamp-Bright-110V-220V-12V/123255156639> What happened was that I replaced about 20 incandescent MR16 lights on some overhead track lighting. The light fixtures were miserably ventilated and were killing 20w incandescent lamps at an alarming rate. Replacing them with LED's was suppose to reduce the heat load. Instead, it melted the plastic case instead of blowing the filament. Burning down the house was averted because the house was full of hot plastic smell and the smoke alarm was screaming. Oops. Moral: The plastic materials used in most LED's are not as heat resistant as the glass and ceramic materials used in incandescent and CFL lighting. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Tim R <timothy42b@aol.com>: May 30 05:59AM -0700 On Wednesday, May 29, 2019 at 11:36:07 PM UTC-4, Jeff Liebermann wrote: > Moral: The plastic materials used in most LED's are not as heat > resistant as the glass and ceramic materials used in incandescent and > CFL lighting. Thanks. There's some good info there. Now having looked at the guts of a number of LED lamps I can see where heat dissipation is more of a problem than I realized. It's probably worse than with CFLs because of the concentrated area where the heat is produced, right? What isn't obvious to me, having looked at the internals, is why the orientation would have more than a trivial effect. That heat looks pretty trapped no matter where the base faces. |
| "Arlen G. Holder" <arlingholder@nospam.net>: May 29 03:38PM On Wed, 29 May 2019 06:12:57 -0500, Foxs Mercantile wrote: > Too busy masturbating listening to yourself spout meaningless bullshit? Is your's the response of an adult, Snit? |
| John-Del <ohger1s@gmail.com>: May 29 01:39PM -0700 On Wednesday, May 29, 2019 at 11:38:05 AM UTC-4, Arlen G. Holder wrote: > On Wed, 29 May 2019 06:12:57 -0500, Foxs Mercantile wrote: > > Too busy masturbating listening to yourself spout meaningless bullshit? > Is your's the response of an adult, Snit? Gosh, if everyone who knows you masturbate while listening to your own meaningless bullshit is a snit, then the web is full of snits. John Snit |
| "Arlen G. Holder" <arlingholder@nospam.net>: May 30 06:30AM On Wed, 29 May 2019 13:39:12 -0700 (PDT), John-Del wrote: > Gosh, if everyone who knows you masturbate while listening to your own meaningless bullshit is a snit, then the web is full of snits. What's amazing is that you, John Del, and Snit, _always_ prove to own the mind of a mere child. I don't even need to prove that since you prove it by what you write. o Just watch. |
| Foxs Mercantile <jdangus@att.net>: May 30 07:50AM -0500 On 5/30/2019 1:30 AM, Arlen G. Holder wrote: > I don't even need to prove that since you prove it by what you write. > o Just watch. You are just another self important bump in the noise floor. Convinced of your own worth. You aren't worth a shit, a you prove it every time you rise to bait. And you own insecurity makes you do it every fucking time. You're pathetic. You honestly believe calling me Snit is going to make anyone think you have anything worthwhile to say? Go fuck yourself. -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com --- This email has been checked for viruses by AVG. https://www.avg.com |
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