[Amps] Fuses
Ian White GM3SEK
gm3sek at ifwtech.co.uk
Sat Jan 8 00:34:30 PST 2011
James R Carr wrote:
>Where pray tell do you get a hydraulic breaker? I have installed
>several thousand over the years but have yet to see one filled with
>oil. As for current limiting devices, the fastest breaker will hold in
>for three to seven full cycles. To be current limiting, a fuse has to
>clear in less
>than 1/2 cycle.
A fuse provides NO current limiting until it blows; and a breaker
provides NO current limiting until it breaks.
A lot of damage can be done in those first few milliseconds, which is
why the fuse/breaker is only PART of the solution.
We always need a surge limiting resistor in the B+ as well, to provide
instantaneous current limiting until the fuse/breaker takes over and
finally breaks the circuit.
--
73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek
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