On Sat, 23 Jul 2011 14:52 -0700, "Harold Hallikainen"  wrote:
>
> By "single pin," I assume that's a single pin at each end. How do these
> work, anyway?

Two ways of doing it, one requires a ground nearby, the reflector
generally. Both can use a non-electronic ballast that has a fancy
transformer with a saturable section to provide a high voltage until
there is current flow through the main choke. A capacitor or two rounds
out the circuit. So they are struck with high voltage. Each start a
little coating on the electrode and there are a limited number of
starts. But just fine for offices and industrial environments where
there is only one start per day.=20

2000 starts is what I have always guessed as a minimum. So the bulb
never gets that in normal use of 250 starts per year, it would take 8
years to fail from starting.

Whenever I am in 220/240 volt countries I see fluorescent bulbs in
continuous service running seemingly forever. Here in 120 volt land they
wear out faster. Or maybe it's just a subjective observation.

Bob

--=20
http://www.fastmail.fm - Access your email from home and the web

--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.