Re new fluorescent lights

John Walker (jorwa@ix.netcom.com)
Tue, 9 Jul 1996 18:21:40 -0700

Barry wrote:

>At my local mega-hardware store they have some big posters and
>displays indicating that if you have "ballasts for residential or home
>use" you must switch to 25W 4' bulbs. Yes, that's 25Watt. I think by
>ballasts for residential use they are describing your standard old
>fashioned ballast meant for 40W CW. Indeed, I almost bought some
>fixtures until i noticed they had imprinted on the side, "not for use
>with 34W bulbs." Only the new E-type ballasts were allowed to be used
with 34W bulbs.

Hi Barry,

I also have been to the mega-hardware store (Home Depot) and when I saw
that they were closing out the standard 40 watt bulbs I bought two
cases. One question though, I thought that both the 25 watt and 34
watt bulbs could be used in the old 40 watt ballasts. Here at work
they are installing 34 watt bulbs in the standard 40 watt fixtures and
they aren't changing the ballasts. Anyone know if this sounds right?
>From what I can tell, the new electronic ballasts operate at
frequencies above 15 kHz making the standard 40 watt bulb about 10%
more efficient.

Ron wrote,

>The 'new' energy efficient T-8 48" bulbs are 32 watt. To make sure
>I didn't lose my mind, I ran to my basement and grabbed one. It's a
>GE F32T8-SPX50 USA 32Watt. This is specifically the lamp recommended
>by Karen Randall, who regularly publishes articles in Aquarium
>Magazines on aquatic plants. The color temperature is 5000K (reference
>to the light spectrum).

Hi Ron,

I pulled out my handy Grainger catalog and proceeded to educate myself
on these "new" T8 (1 inch dia.) lamps, but I still have a question.
Both the standard T12 (1.5 inch dia.) and the T8 have the medium bipin
G13 base. Does that mean that I can interchange T12 and T8 bulbs? If
not, will installing an electronic balast allow me to plug in new T8
lamps to standard T12 fixtures? And finally, I see on page 930 of the
'96 catalog that there are F40T8/SPX50 lamps. These T8 40 watters put
out several hundred more lumen than their 32 watt brothers. Any idea
how long the T8 40 watt bulbs are?

As a side note, it appears (to me anyhow) that in the US the switch is
being made to 25 and 34 watt T12 bulbs, and not to the T8 bulbs.

Trying to find the light :)
John Walker