Fluorescent Lights
Changing all the T12 lights and ballasts in our church to T8s. We have many 4 bulb fixtures that had 2 ballasts per fixtures. We are using single 4 bulb ballasts as replacements. Because of so many fi...
Forum Discussion
If you're just powering two lamps per fixture on a four lamp ballast, there is a slight penalty over using a two lamp ballast in that fixture. But nowhere near the power of powering four lamps. Usually you can find the specs on the ballast documentation which shows power draw with two, three and four lamps. Usually ballasts driving less lamps than designed for will drive the remaining lamps slightly harder (brighter), and that is in the specs too. Typical ballasts drive lamps to .88 power level or ballast factor. Anything above a "ballast factor" of 1.0 (32 watts for 32 watt lamp)is overdriving the lamp. It is acceptable to overdrive the lamp up to 1.20 without negative consequences. In fact it is often done intentionally, replacing four lamps with two and overdriving the two to 1.20. These are called "high ballast factor."
You are right, the T8 electronic ballasts are a completely different animal from the T12 rapid start magnetic ballasts.
When retrofitting fixtures it is always a good idea to replaces yellowed lenses and clean reflectors. Prismatic lenses are more efficient than white opaque. You can easily gain 20-30% efficiency right there.
You are right, the T8 electronic ballasts are a completely different animal from the T12 rapid start magnetic ballasts.
When retrofitting fixtures it is always a good idea to replaces yellowed lenses and clean reflectors. Prismatic lenses are more efficient than white opaque. You can easily gain 20-30% efficiency right there.
