I have about a dozen 4-foot fluorescent shop lights in my basement and garage. They’re all hanging from chains and plugged into ceiling-mounted electrical outlets that are controlled by wall-mounted switches. They frequently have to be replaced because the cheap magnetic T12 ballasts in them go bad. On my last trip to buy a replacement I learned something I didn’t know and you may not either. T12 ballasts and some fluorescent bulbs are being phased out in the U.S. next year (2012) because of higher energy efficiency standards, although some exceptions are being made for residential use.
I don’t know if the residential exceptions will allow you to continue buying cheap ($10) shop light fixtures. I won’t be sorry to see them go because I’m tired of replacing them every 2 to 4 years. I’d already seen the video above and had decided that I was going to start repairing my shop lights with T8 electronic ballasts. So I came home from Home Depot with an $18 replacement ballast, a box of ten 32 watt T8 “daylight” bulbs and a new $30 T8 shop light fixture in case my repair failed.
Repair and upgrade was not that difficult
It wasn’t hard to repair my old shop light by replacing its T12 ballast. But I’m not going to describe how to do it because if you don’t do it right you can turn your shop light into an electrical or fire hazard. If you want to learn how then do a search for “T12 to T8 conversion” (without the quotes) and you’ll find many helpful web pages and videos. But I will give you this advice:
- Make certain you use the proper size wire nuts so there’s no chance your new connections will come apart. Vibrations and temperature changes can cause poor connections to become loose.
- Your new ballast will have to be attached and grounded to your light fixture using sheet metal or self-tapping screws. Make certain they won’t come loose and you scrape the paint off the ballast underneath your screws so they will make a good electrical connection.
- Make certain your power cord’s ground wire is also properly attached to the fixture.
- And make certain you unplug your light before you start working on it 🙂
- A 32 watt T8 bulb is slightly brighter than a 40 watt T12 bulb of the same kind. I’ve begun buying “”Daylight” bulbs because they are much brighter than “standard” fluorescent bulbs and they also seem to make colors appear more accurate. And because they use less power T8 bulbs also produce less heat. Which can be an advantage in air conditioned environments.
- Florescent bulbs dim over time and a T8 bulb won’t lose as much of its brightness as a T12 bulb will. A T12 bulb will lose about 20% of its initial brightness and a T8 will only lose about 10%.
- T12 lamps can flicker, hum and sometimes create a stroboscopic effect because they operate at low frequencies (120 or 100 Hz). T8 lamps won’t because their electronic ballasts operate at much higher frequencies (20,000 Hz).
- T8 ballasts can work at much lower temperatures than most T12 ballasts.
The only disadvantage I’ve seen so far is cost. I don’t remember there being much of a difference (if any) in cost between T12 and T8 bulbs.
But T8 light fixtures seem to cost at least twice as much as T12 fixtures. [Might still be true at Home Depot but Lowes sells a really nice T8 shop light for $15.] I’m also concerned about how long their ballasts will last.