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#24489 - 04/14/03 09:13 PM "Energy Saving" Fluorescent Bulbs
ThinkGood Offline

Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
If a fluorescent fixture calls for 40-watt bulbs, and the 34-watt bulbs are used, what happens?

I saw a warning on a box of 34-watt bulbs that indicates the bulbs are not to be used with ballasts that are not designed for them.

Do these bulbs burn out the ballast?

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#24490 - 04/14/03 09:44 PM Re: "Energy Saving" Fluorescent Bulbs
frenchelectrican Offline


Registered: 02/06/03
Posts: 938
Loc: Wi/ Paris France { France for ...
thinkgood; to answer that question yep it will overheat the redistal ballast or cheap shop light fixures i have alot of them my clents gripe at my butt for this one and i say 34 watts T-12 are good for commercal and industrail fixures and all ballast it will marked down what it can take and what cant take
and the second reason that the 34wattsT-12 are not approve for home useage because the power factor it kinda compated to explain but that main point and many ballast manufacter will warn the same thing too

merci marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

#24491 - 04/15/03 01:46 AM Re: "Energy Saving" Fluorescent Bulbs
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
You will end up burning the tubes AND the ballasts out, in double quick time.
Ballasts are sized to deliver a set amount of current to a particular size(length) of tube.
Hope this helps.
Let's face it, these days if you're not young, you're old - Red Green grin

#24492 - 04/15/03 05:17 AM Re: "Energy Saving" Fluorescent Bulbs
electure Offline


Registered: 12/24/00
Posts: 4226
Loc: Fullerton, CA USA
The 34 watt (4') T-12lamps were designed for use with 40 watt ballasts.
You will not experience problems in a genuine fixture (I'm not sure about the homeowner shoplites, which sometimes are meant to be used with even a 25 watt lamp).
If there were problems, the whole State of California would be dark. We haven't been allowed to use 40 watt lamps for years in commercial applications. To my knowledge,none of the manufacturers even make a 34 watt ballast.
Another case of this is that the 8' T12 Slimline lamp has been reduced from 75 watts to 60, also with the only result being reduced light output and energy savings...S

#24493 - 04/15/03 12:27 PM Re: "Energy Saving" Fluorescent Bulbs
kale Offline

Registered: 11/08/02
Posts: 168
NECA newsletter:
"When energy-saving 34- and 35-watt lamps are used as replacements in these older fixtures, the ballasts may overheat, automatically shutting off the fixtures for safety reasons. While most commercial users understand this problem and have replaced or upgraded their fluorescent luminaires, many household users still have older fixtures designed for 40-watt tubes in their basements, garages, kitchens, etc."

Check out this link for more.

#24494 - 04/15/03 07:00 PM Re: "Energy Saving" Fluorescent Bulbs
HotLine1 Online   content


Registered: 04/03/02
Posts: 6791
Loc: Brick, NJ USA
Long time, no talk.
IMHO, and based on experience...
There are no readily available F40-T12-CW lamps available for sale in the US. Federal Energy Act, heck about 5-7 years ago.

THe mfgs came out with 34 watt, to be installed in the 40 watt fixtures, to save 24 watts in a 4-lamp fixture. Yes, there has been ballast "failure", but I for one have NO proof that the bulb caused the fail.

You may want to e-mail, Phillips, or GE and get a bulb maven to agree with the above. THe same is happening with the 8' T-12 lamps, as stated in another reply. Also, there are changes made to the "HO" 8' bulbs, but that's another "soap box" for me.

As to the "shop lites", there should be no problem with the 34 watt bulb...but remember, you can buy a whole "shop-lite" in a big box store around here CHEAPER than the price of a ballast.

The above are my opinions, and are open for discussion.


#24495 - 04/15/03 08:24 PM Re: "Energy Saving" Fluorescent Bulbs
caselec Offline

Registered: 04/14/02
Posts: 557
Loc: San Jose, CA
Actually 40 watt T-12 lamps are readily available at most retail stores but in limited colors. The most common is cool white deluxe.
When the Federal Energy Act banned 40 watt T-12 lamps there was a small problem. While all of the commercial ballasts have been designed for use with 34 watt or 40 watt lamps for many years the ballasts used in fixtures sold in retail stores had ballasts rated only for 40 watt lamps and are marked "do not use with energy saving lamps". Also dimming ballast will not work with 34 watt lamps. The solution was to allow a limited selection of 40 watt lamps to still be manufactured for replacement use in existing fixtures. If you look in a Philips, GE or Sylvania lamp catalog you will see what colors are available.

Curt Swartz

#24496 - 04/27/03 05:26 AM Re: "Energy Saving" Fluorescent Bulbs
ThinkGood Offline

Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
HotLine1: Hello!

I have a "big box store" shop light that suddenly stopped working--after about a month of use. I checked again and found a label indicating that 25, 34 or 40 watt T-12 bulbs are the only ones to be used. So, I don't think it was the 34-watt bulbs.

Ah, disposable luminaires...

#24497 - 04/27/03 12:06 PM Re: "Energy Saving" Fluorescent Bulbs
rowdyrudy Offline

Registered: 11/02/02
Posts: 171
Loc: Mascoutah, IL USA
I have had 34W lamps in 8 2-lamp fixtures for the past 9 years. Two days ago 1 lamp went south. No problems of any kind as ballasts were designed for 34W lamps.
I have an old fixture from 1962 that just doesn't seem to be quiet when I tried 34W. With 40W its O.K.

#24498 - 04/27/03 03:45 PM Re: "Energy Saving" Fluorescent Bulbs
walrus Offline

Registered: 07/25/02
Posts: 671
Loc: Bangor Me. USA
How do you guys handle old tubes. In Maine they are universal hazardous waste and must be disposed of properly. Which means taking them back to a supply house and filling out paperwork and paying 12 cents a foot. They go a recycler in Mass.
Its a a real hassle, you have to save up enough to fill a box and must designate a lockable location in your shop to store.

Anyone else doing this?

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