Fluorescent Lighting--Cool White vs Daylight Deluxe Style Tubes

[mickyd]

Hi Mike,
That was some interesting reading. I will see what other brands HD stocks and check the specs. I am happy with the Philips daylight tubes , especially when compared to the cool white. What made it nice was the display at the store where you could compare the different types of frosting side by side.---Dave

HD may have thier spec wrong. This sitelists color temp for that same Phillips bulb at 6500K (11240 F) vs. HD listing of 6500F.

[judaspre1982]

===============================

[Ed in Tampa]

When I buy lights I always go by lumens. I have seen florescent tubes labeled all kinds of things but their lumen value is down. Our local HD sells Shoplight or Work light florescent tubes that carry higher lumen values for the same wattage rating than any of the soft white, daylight, real color tubes that I can find in the store.

i know of no florescent tubes that render true color light. Some are closer than others but after seeking lighting for our kitchen remodel and talking to at least 10 lighting experts I was steered to xenon as rendering the truest colors. I guess LED lights beat xenon but they can't be dimmed at this point in time.

[dlbristol]

Lots to learn here! I used the Daylight lamps form HD in my rewire of my shop. I like them, but then about anything was going to better than what I had. I will look at replacement lamps more closely based on what was said here, especially about lumins. My only mistake was not putting 2 units in. I have some shadow issues. I replaced some older lamps over my benchs and that made a world of difference. The old ones were of " unknown"origin, taken from a rental remodel.

[backhertz]

Here something interested about fluorescents:

http://www.goinggreenlighting.com/SAVIN ... TIONS.html

I never knew these suckers used so much power.
Know anything about these LED replacements other
than they are expen$ive?

[reible]

One of my projects over the last few weeks was to do some wattage readings on my shop lighting. I have one of those watt meters so it was simple as plugging in and reading.

I was looking at a couple of things. One was how the newer bulbs I just put in were verses the one put in earlier. There was no differences that could be seen.

When you use the lights does the power level change over time. For this I started the lights and waited one minute and took readings. I checked back two hours later and checked again. Again no difference.

Next was to see if any of the fixtures/bulbs were different then the others. Results was no they all read the same (small sample size I know).

Next was the watt reading for the fixtures. Bulbs are listed as 32 watts and the pair should be 64 watts... actual reading was 60 watts.

Now I wish I had kept some of the old lights to measure.

Ed

[mindpilot]

I suspect the ballast may have more to do with the power consumption than the tubes.

I recently replaced the tubes in my shop because they had grown dim; it didn't change a thing. So more or less as an experiment, I bought a new top-of-the-line, i. e. most expensive one they had, electronic ballast. The ballast cost more than twice the price of a whole new fixture. But man, what a difference!

The tubes were now flicker-free and really bright white. I pulled the old tubes out of the trash and re-installed them; even though they had been in use for several years there was no noticeable difference between old and new.

I went back to the hardware store and bought two more ballasts for the other fixtures and even though the ballasts were close to $30 apiece, it was well worth it. No doubt I'll recoup that cost soon enough since I no longer have to run a pair of 300-watt halogen work lights.

[Ed in Tampa]

Mindpilot
You bring up a good point. I thought ballast comsumed the most power. I fail to understand how Reible is getting his reading. If the bulbs consume 32 watts here has to be lost to ballast.

I know in my lights the old ballast gets fairly hot that energy has to come from somewhere.

Perhaps I don't understand with the wattage stamped on the actual tubes really means. I thought it was how much power the tube itself consumed.

I thought I read in one of these "Green" articles that fluorescents weren't the energy savers many thought because the energy used by the ballast was often ignored.

[dusty]

A ballast is a transformer and as such it does consume energy. After your lights have been on for a while, grab hold of your ballast and see. It will be hot. Hot equals expended energy. The tubes, at the same time, will be warm. Draw your own conclusions.

[JPG]

A ballast is a transformer and as such it does consume energy. After your lights have been on for a while, grab hold of your ballast and see. It will be hot. Hot equals expended energy. The tubes, at the same time, will be warm. Draw your own conclusions.

Ballasts are more 'lossy' than a transformer. They serve two functions - 1)Provide a high voltage(transformer) so the gas in the tubes will ionize and 'excite' the florescent coating on the inside of the tubes 2)limit the current through the tube once ionization is occurring. This is accomplished by the 'transformer' being magnetically inadequate(lossy). In the process of limiting the current, it also gets hot(energy loss). Add to this the fact that the voltage reduction(the current is limited by reducing the output voltage) also reduces the voltage the ballast also supplies to the heater filament, but not to zero, so it still heats some. [this filament discussion does not apply to tubes with single pin on each end(no filament)]

NOW Educate me re newer 'electronic' ballasts I assume from earlier post they are available as a direct replacement for the older ones and do not require a different lamp(tube)? Any correction/additional info???

$30 is not that much more expensive than a 'standard' replacement ballast(IF you can find one) It is cheaper to buy a new fixture and either replace the whole fixture or pull the ballast and install it in the old foxture.