Mike Dolt Enterprises
Mike Dolt Enterprises
User: nizak, Location: NE (9.06 miles @5.9 Degrees from Winged Horses)
Asked on: Wednesday, March 23, 2011 at 9:16 am EDT
Answered on: Tuesday, May 14, 2024 at 3:09 am EDT
Question: I have a lighting rep that is telling me he has a 4' 2 lamp t8 surface mount fixture(4100 series lamps) that will produce the same amount of light as an existing 4' 4 lamp t12 34W cool white fixture. I don't see where he's getting the extra lumens from with just 2 tubes. Any thoughts? I'm finding the t8 lamps produce about 2800 lumens, not sure what the old t12's give out.
It's unlikely that a 4' 2-lamp T8 surface mount fixture can produce the same amount of light as an existing 4' 4-lamp T12 34W cool white fixture. Here's why
Lumens Output:
A typical 4' 4-lamp T12 34W cool white fixture produces around 5,200 lumens. A typical 4' 2-lamp T8 4100 series lamp fixture produces around 4,000 lumens.
Efficacy (Lumens per Watt)
T12 lamps have an efficacy of around 60 lumens per watt. T8 lamps have an efficacy of around 90 lumens per watt.
Number of Lamps
The 4-lamp T12 fixture has a larger number of lamps, which contributes to its higher overall lumens output.
Reflector Design
T12 fixtures often have reflectors that help direct the light downward, increasing the lumens output on the surface below.
Lamp Length
* T12 lamps are longer than T8 lamps, which allows for more space and better distribution of light within the fixture.
Conclusion:
Based on the information provided, it's improbable that a 4' 2-lamp T8 surface mount fixture can produce the same amount of light as a 4' 4-lamp T12 34W cool white fixture. The 4-lamp T12 fixture will likely provide significantly higher lumens output due to its higher number of lamps, higher wattage, and better reflector design. Flag for review