LED tubes

[tabbypurr]

then you're wrong

[invalid]

I have a 10W LED flood light, it takes 10W of electricity. I would expect a 100W flood light to take 100W. The same as I know the 70W LED COB panels I have take 70W.

[alan_m]

If from China the 10W is probably 5W and the 100W would be 50W.

In the BigClive teardown videos he usually measures the power taken by these Chinese sourced products and finds that the quoted Wattage is often twice that of reality.

[The Natural Philosopher]

You believe wrong.

No, the LEDS have an efficiency of around <40%, the PSU will havce an efficiency of aboput 85-99%. Depending.

So 15% of the power at most is lost in the PSU and 40% of the remaining

60% of the remaining poower will be lost as heat in the LEDS.

So for a 6W LED

- at most 0.9W is lost as PSU heat

- more than 3.6W is lost as heat by the LEDS

- *at most* 2.4W goes out as light.

In fcat its generally a lot worse than that as aan incandensecnt lamp is aroind 2.2% efficient and there is no way a 6W LED matches a 100W light bulb!

Infact te ones I jus bougfht are '40W' equivalent whihm neans tehy are at best 24% efficient so about 3/4 of the input power - 4.5W - is going out as heat FROM THE LEDS.

That for electrionics is a fair amount of heat.

Must be a big metal case with lots of surface area then

>

[tabbypurr]

Some folk are optimistic about LED efficiency. You can expect around 100 lpw from good retail LEDs, which is 14.6% of the 100% efficient figure of 683 lpw. The rest of course becomes heat.

100w filament lamps gave about 15 lpw.

NT