On Fri, 04 Oct 2019 23:46:55 +0100, AlexK wrote:



"Commander Kinsey" wrote in message
news
On Fri, 04 Oct 2019 19:17:46 +0100, AlexK wrote:



"Commander Kinsey" wrote in message
news On Fri, 04 Oct 2019 09:41:25 +0100, PeterC

wrote:

On Thu, 3 Oct 2019 19:29:42 +0100, Robert wrote:

On 03/10/2019 14:29, Commander Kinsey wrote:
Why do LEDs generate heat? I want a technical answer not "because
they're inefficient". And will we ever make them more efficient?
Besides the inefficiencies in the LED itself which other posters have
covered, LED lamps have some current regulation or power supply
built-in
which will not be 100% efficient and thus generates heat.

If my meter is correct, all the LEDs that I've measured have a PF of
approx.
0.5 - not a good start.
One TV has a PF of 0.97 and is barely warm over the PSU; another is
0.86
and
is luke warm. The real warmth in the 2nd. one is around the inputs
though -
SPDIF, USB and HDMI.

Is power factor that important? In a domestic building, you are not
billed for power factor. I might have a capacitive load, but my
neighbour
has an inductive load, so they even out.

Most neighbours don't have much long term inductive load anymore.

I don't see why it would have reduced.

It has anyway.

For what reason Mr Speed? You ain't fooling me.

Inductive load is from motors - mowers, washing machines, vacuum cleaners,
etc. This hasn't changed.

The type of motor used in those has tho. Far fewer of the original
motors with a power factor problem now in domestic appliances.

Ah, so you answered it here instead of up there where you interrupted. FFS.