- Lightning Strike - 5 Updates
| "Peter W." <peterwieck33@gmail.com>: Oct 25 10:53AM -0700 > Induction perhaps? Those LED "filaments" form a 1 turn loop of 60 > LED's in series. A lightning strike nearby could create enough of a > field to blow out the bulbs. I would agree with this, but for the fact that the failure modes were not uniform. Some began blinking at turn-on. Two cracked the glass envelope - neatly at the base. Some just never lit. Some got intermittent dark spots on the filaments. My best guess is that there is some sort of driver element(s) in the base that were affected.... When I am back on my feet, reliably, I will slit one with the Dremel and see what gives. Peter Wieck Melrose Park, PA |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 25 02:54PM -0700 On Mon, 25 Oct 2021 10:53:28 -0700 (PDT), "Peter W." >> LED's in series. A lightning strike nearby could create enough of a >> field to blow out the bulbs. >I would agree with this, but for the fact that the failure modes were not uniform. LED's and diodes usually fail by shorting out. Once one diode is shorted, the current increases causing the next diode in the string to short. This continues until the current is high enough the blow up a thin wire or trace, usually in the base. If you have a microscope handy, you can possibly visually distinguish between the good and shorted diodes. >Some began blinking at turn-on. Current regulator device or circuit might be oscillating. <https://en.wikipedia.org/wiki/LED_filament> "The simple capacitive or resistive dropper power supply used by some cheaper bulbs will cause some flickering..." >Two cracked the glass envelope - neatly at the base. The glass envelope is sealed. Sudden rise in internal gas pressure might cause the envelope to explode. >Some just never lit. Simulated a fuse? >Some got intermittent dark spots on the filaments. I have some bad guesses for what caused that. Maybe later. >My best guess is that there is some sort of driver element(s) in the base that were affected.... When I am back on my feet, reliably, I will slit one with the Dremel and see what gives. Autopsy. Some design details here: <https://en.wikipedia.org/wiki/LED_filament#Design> <https://patents.google.com/patent/US8400051> -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
| Mike S <mscir@yahoo.com>: Oct 25 09:09PM -0700 On 10/25/2021 2:54 PM, Jeff Liebermann wrote: > <https://patents.google.com/patent/US8400051> >> Peter Wieck >> Melrose Park, PA Interesting discussion, I'm looking fwd to followups. I looked around online a little but and nobody I read seemed to think a lightning arrestor on the neutral would be of any use, but I don't know myself, here to learn. |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 25 09:53PM -0700 >online a little but and nobody I read seemed to think a lightning >arrestor on the neutral would be of any use, but I don't know myself, >here to learn. Where would you ground or connect such a lightning arrestor? The neutral (white) wire is always connected to earth (green) ground at the main electrical panel. Installing a lightning arrestor across ground to ground is not going to do anything useful. More than you probably wanted to know on electrical grounding: <https://en.wikipedia.org/wiki/Ground_and_neutral> -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
| KenW <ken1943@invalid.net>: Oct 26 06:30AM -0600 On Mon, 25 Oct 2021 21:53:44 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >ground to ground is not going to do anything useful. >More than you probably wanted to know on electrical grounding: ><https://en.wikipedia.org/wiki/Ground_and_neutral> In my first home an arrestor ? was installed in the electric panel when I updated to 200amp service. 30 +/- years ago. KenW |
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