Peter Taylor wrote:

I was once told that fluorescent tubes use the same amount of power during
start-up as they do in 45mins normal running time. In other words, in power
terms it's not worth switching on or off a fluorescent tube unless it will
be on/off for at least 45 minutes.

For a 3 second startup time and a 60w tube, ignoring ballast losses, to
meet that claim the starting power would need to be 45 x 60 / 3 x 60w =
54kW (around 200A per tube). Coincidentally, more power than rotates a
turning bridge.


NT