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.

On 5/3/2020 5:47 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.


Perhaps it has more to do with the reflector than the electronics.

Too light and it may need a cancer warning label. ;~)

On Wed, 6 May 2020 09:17:27 -0500, Leon lcb11211@swbelldotnet wrote:

On 5/3/2020 5:47 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.


Perhaps it has more to do with the reflector than the electronics.

I'd thought of that, though the plastic diffuser. There is no
reflector, other than the white interior (it's an untra-cheap
fixture).

Too light and it may need a cancer warning label. ;~)

Californica, for sure.

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.

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.

Hawk writes:
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

Highly unlikely, even assuming one can wade through all the non-topic garbage.

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.

The ballast care about the power consumption (watts) of the tube(s), which
typically range from 65 watts to 110 (usually labled HO, or high-output on
the bulb) watts. The color temperature doesn't generally change the wattage
requirements, but other factors (producing more light with weaker phosphor)
may require the bulb to consume more power. The ballast will be labeled as
to how many watts it supports and the bulbs will list their power consumption.

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.