T12 and T8 bulbs interchangable?

Calab

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Feb 1, 2008, 1:24:51 PM2/1/08

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I have several four foot fluorescent light fixtures in my basement. I
recently found that some are marked that they take either T12 or T8 bulbs.
Several others are not marked and currently have T12 bulbs.

Are these bulbs interchangable, or with T8 bulbs only go into specific
fixtures?

I intend on opening up the fixtures to check the ballasts next time I'm up
in the ceiling, but I'd like to know.

RBM

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Feb 1, 2008, 1:30:16 PM2/1/08

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I think that some of the new ballasts will work with both. If so, it'll say
so on the ballast case.

"Calab" <mys...@csd.ca> wrote in message
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RBM

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Feb 1, 2008, 1:39:05 PM2/1/08

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The older magnetic ballasts are pretty limited as to which lamps will work
but the new electronic ballasts handle a much wider spectrum. Pretty soon
there will be "one ballast fits all"

"Calab" <mys...@csd.ca> wrote in message
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SBH

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Feb 2, 2008, 7:12:47 AM2/2/08

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"Calab" <mys...@csd.ca> wrote in message
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No, they are not. Even with the electronic ballast, they will not work for
both. You will notice the ballast model number/letters on top. It'll usually
read F32T8, or something along those lines, indicating the length and type
of bulb.

A universal ballast can usually be used for one or two bulbs and can work
with 120volts to 277volts. But they are not universal for T12 and T8.

RBM

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Feb 2, 2008, 7:27:55 AM2/2/08

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"SBH" <Mea...@bluebottle.com> wrote in message
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Completely incorrect answer: Here are the specs from a Keystone ballast:
KTEB-240-1-TP /C (Electronic Fluorescent, 120V)
2x CFQ26W/G24q , CFTR32W/GX24q , F25T8 , F30T12 , F32T8 , F34T12 ,
F40T12 , F40T12 (25W)

>
>

SBH

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Feb 3, 2008, 9:56:51 AM2/3/08

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"RBM" <r...@noemail.com> wrote in message
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> Completely incorrect answer: Here are the specs from a Keystone ballast:
> KTEB-240-1-TP /C (Electronic Fluorescent, 120V)
> 2x CFQ26W/G24q , CFTR32W/GX24q , F25T8 , F30T12 , F32T8 , F34T12 ,
> F40T12 , F40T12 (25W)
>
>>
>>

My apologies. We come across many types of ballast within my employment and
have yet to see one which will work for a T12 and T8, though many will work
on a voltage range and bulb quantity. Therefore, I did not think they
existed, just yet. I stand corrected.
>

RBM

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Feb 3, 2008, 10:36:44 AM2/3/08

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This is all new stuff. I was serious about one size fits all ballasts coming
soon

"SBH" <Mea...@bluebottle.com> wrote in message

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TKM

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Feb 4, 2008, 11:06:36 AM2/4/08

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"RBM" <r...@noemail.com> wrote in message

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Check out the fine print too. It's at:
http://www.keystoneballast.com/techdocs%5CKTEB-240-1-TP.pdf
If you just want the tubes to light up, fine. If you want them to operate
at manufacturer-rated values, then look further.

The ballast operates standard 4-foot F40T12 lamps at 75% of rated output,
but standard F32T8 lamps at 5% more than the rated value.

TKM