41–50 of 519 posts
I once worked for an offshoot of Sunfor - a chemical company making LED phosphors. The first driverless, flicker free LEDs on the market were their invention. Basic idea is that if you fine tune phosphor components, and their ratios, you can make a direct 120hz AC driven LED with close to no visible flicker for as long as your output colour temperature is in between 5500 to 6000 Kelvins
Personally I love the heat that an incondecent bulb emits, I can actually keep my hands warm on my keyboard while lowering my room heat. 75 watt bulb with heat versus a 3000 watt space heater.
It separates the light and heat concerns.
I've taken every single LED bulb that has failed on me to pieces and it's always the same failure mode. The heatsink compound isn't applied properly to the back of the LED board. The LEDs immediately in the gaps smoke out. Alas this isn't a problem. If a lightbulb goes, Amazon send me a new one out now free of charge and tell me to throw the old one in the trash. This is one manufacturer, prevalent on Amazon, the Lon…
They've run cheap and cold for years now, without a single failure.
I suspect that there's some planned obsolescence in newer products.
0: https://www.amazon.ca/gp/aw/d/B01EN9L8YU?psc=1&ref=ppx_pop_m...
My father in law is a general contractor and religiously keeps all his LED bulb receipts. If anything goes out before the listed hours he returns it to HomeDepot. He hasn’t had any issue so far including some of the older bulbs described in the article.
This makes me wonder if we shouldn't have an AC and DC circuits in the house. I mean, it could be all AC coming in, but at the box it splits into (at least) two different circuits (an AC one and a DC one). AC circuit would still be used for things that have motors, but everything else uses DC. Imagine how simple LED lighting could be on a DC circuit. Just an LED and resistor. I only took a few electrical engineering…
High voltage DC is not useful for the things people use.
I also have been disappointed with LED "bulbs". They get too damn hot in recessed fixtures but NOT because of the LED's. It's all because of the shitty power converter embedded deep inside the bulb getting too hot and failing. The industry has necessarily had to retrofit to where incandescent bulbs are supposed to go. I think that we'll start to see improvements in this area as people move away from "screw-in bulb" a…
Every so often, I come back to the "I should have DC power on demand in my house!" until I'm reminded that DC power loss over a distance can hurt bad, even 48VDC telecom power. Perhaps USB-C PD might help? USB power adapters are compact and PD offers standard, useful high power DC. If the adapters become ubiquitous, you could see "USB-C lightbulbs".
This makes me wonder if we shouldn't have an AC and DC circuits in the house. I mean, it could be all AC coming in, but at the box it splits into (at least) two different circuits (an AC one and a DC one). AC circuit would still be used for things that have motors, but everything else uses DC. Imagine how simple LED lighting could be on a DC circuit. Just an LED and resistor. I only took a few electrical engineering…
I also have been disappointed with LED "bulbs". They get too damn hot in recessed fixtures but NOT because of the LED's. It's all because of the shitty power converter embedded deep inside the bulb getting too hot and failing. The industry has necessarily had to retrofit to where incandescent bulbs are supposed to go. I think that we'll start to see improvements in this area as people move away from "screw-in bulb" a…
Every so often, I come back to the "I should have DC power on demand in my house!" until I'm reminded that DC power loss over a distance can hurt bad, even 48VDC telecom power. Perhaps USB-C PD might help? USB power adapters are compact and PD offers standard, useful high power DC. If the adapters become ubiquitous, you could see "USB-C lightbulbs".
If you had AC to your house, then a rectifier for a 100V/200V DC circuit through your house, the losses wouldn't be any worse.
DC losses are less than AC losses at the equivalent voltage, because the resistance seen by DC is less than the AC impedance.
I also have been disappointed with LED "bulbs". They get too damn hot in recessed fixtures but NOT because of the LED's. It's all because of the shitty power converter embedded deep inside the bulb getting too hot and failing. The industry has necessarily had to retrofit to where incandescent bulbs are supposed to go. I think that we'll start to see improvements in this area as people move away from "screw-in bulb" a…