On Wed, 6 May 2020 14:05:45 -0400, Hawk wrote:

On 5/3/2020 6:47 PM, wrote:

I just read the instructions (dumb idea, I know) for some fluorescent
fixtures I bought sometime back, for my shop. Anyway, it says the
fixture is only for 2700K, 3500K, and 4100K tubes. Why does the
fixture/ballast care what phosphor is in the tubes? I was planning on
using 6500K tubes (like I have in similar fixtures). If there is good
reason to respect these instructions, I'll probably change them over
to LEDs but it's a lot of tubes to trash. The coldest white LED tubes
I've seen are 5000K. I'd prefer 6500K but 5000K would probably work.


You'd probably have a greater response in the alt.home.repair group but
as far as I know from working with lamps and fixtures for many years,
the K value does not have a major impact on energy usage. I would not
know why they establish a limit.

Seems dumb to me.

IMO, there isn't much of a difference in brightness with 5000K and
6500K. The difference with the higher number will be a bluer hue. I have
use 5000 in most areas of my home and very happy with the results.

I disagree. There is a huge difference in, at least the perceived,
light output of the hotter tubes. That's why they're used in
industrial applications.