On Jun 16, 2008, at 9:59 PM, <[EMAIL PROTECTED]> <[EMAIL PROTECTED]
> wrote:
A regular fuse should blow at 2.6 x the rating within 30s, in other
words very slowly. It's only a short circuit that will normally
blow a new fuse. Have not seen any data on old fuses which might
get metal fatigue. There are faster fuses, but the fastest are rf
transistors - on three legs anyway...
Most people don't know that the purpose of a fuse or circuit breaker
is to protect the power distribution wiring, not the electronic
component itself. Wire will carry a surge without too much temperature
rise. The idea is that the fuse will blow or the breaker open before
there is any chance of damage to the wire.
This means that a fuse or breaker cannot protect your active devices.
If you want that level of protection you need something like a power
supply with fold-back current limiting.
Brian Lloyd
Granite Bay Montessori School 9330 Sierra College Bl
brian AT gbmontessori DOT com Roseville, CA 95661
+1.916.367.2131 (voice) +1.791.912.8170 (fax)
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
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