Fluorescent Tubes

[Little Bill]

What exactly happens inside a fluorescent tube when it fails? I'm guessing the phosphor (or what ever) burns up or is depleted. Also, does the blackened end indicate that? Trying to explain this to a customer.

 

[zbang]

I was told that like an incandescent lamp, the electrode material depletes and is deposited on the tube walls, hence the blackness. Not enough electrode, not enough electrons to make enough light. Don't know how true that is.

 

[cadpoint]

I really like the internet at times.... a nice ten page PDF on Fluorescent Lamps
This has some nice colored graphics too...

ANALYSING THE CAUSES OF BLACKENING OF ENDS OF FLUORESCENT LAMPS.

Seems Zbang heard it correctly.

 

[zbang]

Wow, that thing "a man in the pub told me" (er, "the foreman told me") is actually correct .