[oceanus]

Hi All, my first post.

This is a great thread that got me working on my personal OD project, which I just completed.

This weekend, I retrofitted a similar setup and got some results that seem to back up the original findings in this thread.

The set up is:

1 - Advance REL-4P32-SC (4x32W)
3 - Philips T8 48" Daylight 6500K bulbs in the following configuration:
1st bulb - normal output (1 lead)
2nd bulb - normal output (1 lead)
3rd bulb - overdrive 2x (2 leads)

Due to way the hood is set up, the wiring is permanent, so I can only test according to the on/off combinations above by removing or adding bulbs.

Using the kill-a-watt device (which I love), I got the following wattage consumption measurements:

a) No bulbs installed: 5 watts
b) Only 1 NO bulb: 40 watts
c) Only the 2xOD bulb: 54 watts
d) Both NO bulbs: 66 watts
e) One NO and the 2xOD: 80 watts
f) All three bulbs: 102 watts

With all three bulbs on, the 2xOD bulb is noticibly brighter. Unfortuntely, I don't have any light measuring equipment, so that desciption is as scientific as it's gonna get. Thats a shame b/c while the 2xOD is brighter, I don't know if the 2xOD brighter b/c of pure additional lighting, or if it was somehow stealing something from the other bulbs and making them dimmer.

The ballast was plugged into the kill-a-watt device, which in turn was plugged directly into a wall socket.

Any comments, questions or suggestions?

Thanks

Switching into a electronic ballast rather than a noraml ballast will helps save at least 30% of the electricity consumption as well..

 

[paulrw]

so what about overdriving a standard t-5 ballasts and bulbs i'm o.d.ing a standard t-5 x2
28w bulb it looks a little brighter and a little whiter can i expect better results useing this bulb instead of a factory o.d. 54w bulb

 

[veganboyscout]

hey Shalu, I think you were using the wrong formula to calculate "OD Efficiency" in column 5. I believe you should have divided the lumen/watt figure by 1, 2, 3 or 4 X the lumen/watt figure for the 1 X test (respectively). For example, The "OD Efficiency" for the T8 bulb at 4X overdrive should be 4.6/(4x3.8)=.30 According to your data, you should have concluded that T8 bulbs at 4X overdrive are less than 1/3 as efficient as 1X factory T8 bulbs. Your conclusions were completely wrong. Fluorescent bulbs do become markedly less efficient the more you overdrive them, not more! Your own data demonstrates that! I wish you were right, but you are not. Does anybody else agree with me?

 

[veganboyscout]

Shalu, I thought some more on these calculations, and I realized that when calculating the efficiency we should use the proportion that the wattage increased, not the 1x, 2x, 3x, 4x because the power did not increase in practice or in reality by double, triple, quadruple, as we attempt to do by overdriving the lights. We know this thanks to your use of the Kill-A-Watt. So, for the T8 bulb at 4x overdrive, the OD Efficienies calculation would look like 4.6/(3.8*(69/40))=.70 or 70% efficiency. So, as 100% efficiency for 1x as the basis, for all the T8 OD Efficiencies, I calculated 2x = 85%, 3x=78%, 4x=70%. These figures are in agreement with estimates elsewhere on the web.