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New LED lights reliability

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james_s:

--- Quote from: Marco on February 08, 2019, 03:35:29 am ---Why would a proper high frequency driver be large?

--- End quote ---

Generally because inductors and electrolytic capacitors are relatively large, and high frequency drivers typically have at least one of each of those. Note that "large" is relative to the linear driver ICs used in most of the filament style bulbs.

OwO:
LED bulbs that are actually bright run too hot, and LED bulbs that last long are not bright enough.

The efficiency of LEDs max out at <50%, so there is no way around the power dissipation problem. Even the most efficient 6W bulbs are nowhere near bright enough, so you need >5 of them for a typical bedroom. This is grossly suboptimal because instead of having one PSU/driver you have 5 of them, and each crammed into a tight space with LEDs running at 60 degrees C which does not bode well for the lifetime of the electrolytic capacitors.

james_s:
I simply don't find that to be the case. My bedroom ceiling light has 3 early Philips 8W remote phosphor lamps, they are plenty bright and have been in service for 8 years now. The fixture in my hall has a pair of 6.5W 800lm filament style bulbs, again plenty bright. Over the dining table the fixture has 5 sockets with Philips 10.5W LED bulbs, they're way too bright at full brightness so they're on a dimmer and run typically at about half brightness. The bathrooms and several other rooms are lit by pairs of early Philips 12.5W bulbs, I've never had one of those fail. It feels like I've gone back in a time machine, people talking like bulbs don't exist yet that I've already been using for the better part of a decade. 100% of the Edison base fixtures and lamps in and on my house have been fitted with LED bulbs for years now, at least 30 bulbs in total, they're bright and reliable.

NiHaoMike:

--- Quote from: OwO on February 08, 2019, 05:03:37 am ---LED bulbs that are actually bright run too hot, and LED bulbs that last long are not bright enough.

The efficiency of LEDs max out at <50%, so there is no way around the power dissipation problem. Even the most efficient 6W bulbs are nowhere near bright enough, so you need >5 of them for a typical bedroom. This is grossly suboptimal because instead of having one PSU/driver you have 5 of them, and each crammed into a tight space with LEDs running at 60 degrees C which does not bode well for the lifetime of the electrolytic capacitors.

--- End quote ---

--- Quote from: james_s on February 08, 2019, 05:28:18 am ---I simply don't find that to be the case. My bedroom ceiling light has 3 early Philips 8W remote phosphor lamps, they are plenty bright and have been in service for 8 years now. The fixture in my hall has a pair of 6.5W 800lm filament style bulbs, again plenty bright. Over the dining table the fixture has 5 sockets with Philips 10.5W LED bulbs, they're way too bright at full brightness so they're on a dimmer and run typically at about half brightness. The bathrooms and several other rooms are lit by pairs of early Philips 12.5W bulbs, I've never had one of those fail. It feels like I've gone back in a time machine, people talking like bulbs don't exist yet that I've already been using for the better part of a decade. 100% of the Edison base fixtures and lamps in and on my house have been fitted with LED bulbs for years now, at least 30 bulbs in total, they're bright and reliable.

--- End quote ---
I have to agree that if it's just a normal bedroom only used as a bedroom, something like 5W of LED lighting is plenty to not run into things while going to bed. If having to get up in the middle of the night, even 1W is unpleasantly bright and a single 5mm LED is about perfect.

Marco:

--- Quote from: james_s on February 08, 2019, 04:21:43 am ---Generally because inductors and electrolytic capacitors are relatively large, and high frequency drivers typically have at least one of each of those. Note that "large" is relative to the linear driver ICs used in most of the filament style bulbs.

--- End quote ---

6.8 uF electrolytic is more than enough to keep the rectified voltage above 110V and fits just fine in E27, same goes for an inductor for a ~100 kHz buck converter.

Even film capacitors would probably fit, but it would be much more expensive.

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