On Mon, 24 Feb 97 15:05:35 PST mrice@mindscape.com writes:
> When resistors are placed in Series, isn't the string limited
> to the current rating of the least of them?
No, the string is limited by the POWER rating of the least of them. You
were unfortunately looking at fuses, which are rated for a given current.
Those fuses are really resistors, but resistors with a very low (but
finite) resistance. And your little experiment showed you that the
"resistor" with the lowest POWER rating will fail first. The effect in
fuses is magnified by the fact that a lower current rating in a fuse
means a smaller conductor (actually fine wire on those fractional-amp
fuses), and therefore a higher resistance, so they will have a higher
voltage across them relative to the other "resistors" (fuses) in the
string. So the lowest value fuse also dissipates the most power of
those in the string, since the same current flows through each one.
And low and behold, all that power vaporizes some of that wire that
makes up the fuse.
Go back and re-read those answers. Someone (?Mike Gipe) had a beautiful
description, better than I can do. And look in the handbook. Like
the Junior Woodchuck manual, our Handbook has practically everything in
it.
....Reading further down the mail, I see Mike has already answered you,
and I am now pretty sure it was his post I remembered. Go back and
re-read his first post, too.
73, ; D DWink@Juno.com Dan Winkler N7IVR Seattle, WA
----------whom the gods would destroy, they first make proud ----------
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