On 03/06/2017 08:57 PM, Eric Christopherson via cctalk wrote:
I assume the kind of LEDs under discussion doesn't have the problem of
overheating that some LEDs have when placed in enclosures without heat
sinks, right?
The 48" LED fluorescent retrofits have a lot of surface
area, so they probably do OK. The retrofits I made are
electrically isolated from the line, and have 88 square
inches of copper PC board material to act as a heat sink.
They still run quite warm, although when on, the optical
output of these things is stronger than full sunlight, so
they appear to be REALLY warm on the skin, so that fools
you. You have to test the temperature just one second after
they are turned off to get a better idea of the real
temperature.
I'm running about 19 W total into 20 1W LEDs, replacing TWO
48" tubes. Previous input to a 2-lamp ancient ballast was
103 W, the LED supply draws 21 W, as measured with a real
power meter.
Jon