"Andrew Gabriel" wrote in message
...
In article ,
"G&M" writes:

"Grunff" wrote in message
...
Again, I've found this to vary greatly between makes. Some are very
poor, taking 10mins or more to reach max output, while others do so in
a
few seconds.

The time is actually programmed in by the manufacturer. Most now use
the
STMicroelectronics chip and it is easy to set this from 1 second to
days.
The slower it turns on the longer the tube will last.

You are referring to the preheat time (normally around a second).

0.8 second to be precise. But no, I was referring to the auto frequency
ramp up the latest chips provide which allows the lamp power to also be
ramped up independent of the mercury state, though of course this is done
primarily to allow the vapour to diffuse fully through the tube before full
power is applied. These bulbs are identifiable as when you switch them off
and on they still ramp up to full power, though at a faster rate than from
cold, whereas with previous generation devices the warm bulb will come on
full after the preheat.