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Fuses...



>From richard.quick-at-slug-dot-org Tue Aug 29 13:21 MDT 1995

>Thanks for the input on the breaker types and designs.
	you're welcome....

>So what about fuses?
	DON'T hit them with a hammer.  Makes the shell go ..  errr  wrong
	list.....  8)>>

	Simpler, thus, more reliable.

	Same comments re they DO have a (small) series drop, and
	They DO come in varying time delays to operate.

	Cheap.  Arguably, many breakers should have a fuse, rated a bit higher,
	in series with the breaker.  If the breaker DOESN'T, then the fuse
	will.  (This is not uncommon in power compnay wiring, i believe.)

	Same comments on interupting voltage.  A fuse rated for 32vdc may just
	sit and sizzle while trying to interupt 240 vac.

	In applying either breaker or fuse, some thought about "what happens
	to the clydesdale?" can be useful.  Some Power Co fuses/breakers
	have resistors in parallel, sometimes built in.  Thus the energy
	"stored" in the current flow goes up in the resistor as heat, rather
	than appearing as an arc.  In this case a separate, "cold" main
	disconnect is a must, as even with the breaker, etc "open" the resistor
	will leave the circuit live, at low levels.

	regards
	dwp