It is probably
possible to build a current limiter that provides
immediate visual feedback. I challenge you, or anyone for that
matter, to come up with such a design that is as cheap, easy,
simple, and foolproof as an incandescent bulb.
How's this? Grab a glass jar,
fill with water and a salt of your
choice, say, bicarbonate of soda, drop two electrodes into it
(stainless steel or carbon is good; aluminum will tend to polarize
after awhile and form a leaky rectifier). Apply current and watch
for bubbles and/or steam. Vary resistance by varying the distance
However, it tends to produce an explosive atmosphere. It also is
substantially slower to produce visual feedback, and requires looking
fairly directly at it to see the feedback (which is true of
incandescents only for the low end of the current range).
What I don't like about incandescents used as a
load-limiter is the
very low cold resistance. I'd much rather have a "soft" start--but
then carbon-filament incandescents haven't been easy to find for the
last 80 years or so.
If you don't like the cold inrush, maybe you should get that 144 ohm
100 watt resistor I mentioned...and parallel it with some kind of
voltmeter, maybe as simple as a diode bridge, resistor and meter
Seems to me that, at least for power supply applications, a cold inrush
is actually a good thing, since it gets the smoothing caps up to
voltage faster - and doesn't last long.