On Jun 7, 1:41*pm, (Don Klipstein) wrote:
In article , Edee em wrote:
Thanks for the replies!

The fixture is 2' x 2', it has two u-shaped tubes. *I see one ballast but
nothing resembling a "starter". *I would say the fixture is about 20 years
old. *I tried fresh bulbs but the same thing happened.

* If both bulbs were replaced with known good ones, and they come on
dim/flickery, and you know they are compatible with the ballast, chances
are the culprit is the ballast.

* If you replace the ballast, make sure the new ballast and bulbs are
compatible with each other. *There are several different wattages for
4-footers (including U-bent ones 2 feet long). *The 32 watt 1-inch-dia.
and the 40 watt 1.5-inch-dia. bulbs are not electrically interchangeable.

* Another thing I have noticed: *34 watt bulbs in my experience are more
likely to be "cranky" than other wattages of 4-footers. *Also, some
ballasts for F40 are only rated for use with "true 40 watt" ones and could
overheat and/or have shortened life with 34 watt ones.

* If you replace the ballast, best bet is to get a good 32 watt electronic
one such as Sylvania "Quicktronic" or the like from an electrical/lighting
supply shop.
* And my favorite bulbs are ones with 835 or SPX35 color (3500 Kelvin, CRI
in the 80's - highest available without compromise of light output).

*- Don Klipstein )

Does using an electronic ballast require the use of different tubes
than using old fashioned 'regular' ballasts in good condition?
Reason to ask is that I have a batch of used fluorescent fixtures, in
excellent condition except for a few scratches, from renovations at a
school. (They would have been dumped if had not taken them).
Most, but not all of the tubes were missing/broken so replaced with
same type, which for these fixtures equipped with electonic ballasts,
are the thinner and IIRC are T10 type.
But experimentally the older fatter 34 or 40 watt tubes will also
work; but might overheat the 'electronic' ballasts????
Any advice welcome. TIA
terry