On Saturday, July 20, 2013 3:06:47 PM UTC-5, Home Guy wrote:
Meanie wrote:



What exactly would happen if T-8 ballast is connected to a bunch

of T-12 tubes?



If you run a t8 bulb on a t12 ballast



Not interested in that situation.



If you run a t8 ballast running a t12 bulb you will have premature

ballast life as the t12 bulb takes more to run and will over work

the ballast.



I'm not sure if I buy your arm-chair or seat-of-the-pants explanation.

Without solid engineering data, I could just as easily suppose that the

extra few watts used by a T12 tube can be easily handled by the

circuitry of a T8 ballast.



T12s are becoming obsolete. Buy t8 ballasts and use t8 bulbs.

They are brighter and more efficient.



I'd have to do more research on this, but I'm guessing that T8 tubes are

NOT more efficient than T12 (in terms of watts per lumen), and that the

only purpose of T8 replacing T12 is part of the energy politics

happening in western countries - other examples of which is subsidized

CFL's and the ban on sale of 100 watt incandescent.



In other words, the "powers that be" have deemed that we don't need 40,

36 or even 34 watt T12 tubes, and that for the good of the planet, our

eyes have become more efficient and 32-watt T8's are now good enough for

us.



Around here, the largest box of T8 I can buy is a 10-pack, and it costs

about $34.



There are far more boxes of 30-count T12's on the shelves, and they cost

about the same as a 10-pack of T8's.



So tell me again why I should be paying 3X the price for T8, and get 11%

less light in the process?



And I still want to know if they ever made 4-tube electronic ballasts

for T12 tubes.



Given that I can buy a 4-bulb T8 ballast for just about the same price

as a single 2-bulb T12 ballast, it's worth the experiment to run a set

of 4 T-12 tubes off a ballast thats spec'd for T8 tubes.


First of all, there IS a 4 lamp T12 Ballast. There are several manufacturers that make them. However, no one wants to pay the price for them. The Cheapest route for that is to just use two of the 2 lamp T12 ballasts.
Fulham makes a great universal ballast. They work on any lamp up to a certain wattage.
As far as the wattages for the T12 lamps, there IS a 40 watt 4' T12 lamp.. It is a F40T12.
Also, There will always be T12 lamps. They are NOT getting rid of them. Our lovely government has put new guidelines on the manufacturers to make the lamps more efficient. Basically the government says that all fluorescent bulbs must have so many lumens per watt. So now, T12 lamps cost just as much as a T8. Previously we had a F34T12/DX, now since the new government guidelines have gone into effect the new lamp is a F40T12/865. Same thing, just new number....