On 7/31/2017 4:52 PM, Ed Pawlowski wrote:
On 7/31/2017 2:12 PM, Keith Nuttle wrote:
I am posting this to the woodworking group because wood workers know a
lot about everything. ;-)

I am a volunteer at church and one of things that I do is change the
florescent lights when they die. Most of the fixtures are four tube
fixtures.

Is there a test to tell if a Florescent light tube is bad and needs to
be replaced, or the light is not working because its companion is dead?

I have struggled with this. Sometimes when one of the tubes is
replaced the other seems to start working. So it would be nice to
test the tube to see if even though working it should be replaced.



It has been proven by a few studies in plant and office operations that
all bulbs should be replaced at the same time. They have a different
situation in that they have a paid maintenance crew but the economics of
time and getting equipment to the site you do it all. Some
manufacturing companies will do an entire section of a building once a
certain amount of lamps are out. Of course, they are using lifts to get
to 20' or higher ceilings.

I don't worry about testing. I replace them all at the same time.

The key point is location of fixtures and type of lamps. T-8 lamps don't
require all to be replaced if one fails. Though, if location is high
which requires anything beyond an 8 foot ladder, then yes, it is
recommended to replace all.

In high bay areas, we often do a complete relamping when the % of lamp
failure is 20 or more of the total quantity. This partakes several years
apart. But now going to LEDs, we're hoping that problem partakes much
longer with a total LED relamping.