i was going to change the fluorescent T12 fixtures about my home with T8 fixtures, yet I noticed that the T8 bulbs seem to fit simply fine into the T12 fixtures. It seems favor I can save myself a few bucks and maybe some hassle if I simply replace the ballasts instead of replacing the whole fixtures. Plus, I can make sure to to buy higher-efficiency or higher-quality ballasts rather of simply using whatever secret ballasts come with the fluorescent fixtures at the home improvement store. Is over there anything wrong with this plan?

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request Jun 14 "14 in ~ 1:09

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Disagree that T8 ballasts space a far better ballast. Where I work, we're replacing T8 ballasts every 1 come 5 years. The old T12 ballasts that room coming out have been there for at the very least 10 years, and also some as lengthy as 25-30 years, and those were still working when removed. Yes, T8 ballasts room lighter weight, and may be more efficient, however do not last as long as the old T12 ones.
Dec 27 "15 at 16:52
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Replace ballast and lamps, and also for extra savings, ~ above a four tube every bay fixture, gain a 3-lamp ballast and run just three tubes.

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The extra effectiveness of the smaller tube plus high-frequency digital ballast way that 3 T-8 tubes can put out virtually the very same light as 4 T-12 tubes.

The ballast tends to be a lot of smaller, and also weigh much much less than the t-12 ballasts.

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Wiring different -- your ballast will have actually a wiring diagram. Yet to provide you an idea, here is an instance of wiring because that an instant-start electronic ballast (which are less complicated to wire, however tend come fail bulbs faster); and a rapid-start or programmed-start digital ballast (which regularly matches the old magnetic ballasts):


For the smaller 18AWG solid-core wires in ballasts, don"t use the typical yellow/red cable nuts. Usage blue wire-nuts, or because that instance, push-in wiring connectors such together Gardner Bender PushGard, others room available... Make sure the size is correct because that 18 AWG wire.


You can reduce number of bulbs, due to the fact that T8s are brighter. A complete structure rewire from 4 T12 to three T8 tubes per fixture removed 38 tubes and also at 32W each, was a save of 1216 watt in strength reduction if you just count pipe elimination and not likewise ballast effectiveness over mangetic (est. 10-15w every ballast replaced). PLUS, NO FLICKER! for someone with quick vision, not seeing 60Hz flicker in the peripheral vision was practically worth more than the strength savings.