Jerry Kaidor writes:
>Roger Garnett writes:
>
>>(Don't use 125/250V fuses in your car- they are designed differently)
>
> What's the difference? Seems to me that 10 Amps is 10 amps,
>regardless of its height above ground. I can see where a 32 Volt fuse
>might arc over after it blew in a 240 volt circuit, but what difference
>can it make the other way? (Besides, maybe, the 240V fuse not fitting
>in the automotive fuse holder...)
Uhh... ever stick a 12 volt power supply on a 3 volt lightbulb?
10 Amps is 1250 watts at 125 volts. If the resistance on the fuse
is, say, .1% of the total resistance on the circuit, we're talking
a 1.25 watt lightbulb, equivalent to about 400 mA @ 3 volts.
At 12 volts, however, this is .125 watts, which may not even be
warm.
Counting in the other direction, then, a 125V 10 amp fuse will take
about 4x as much current at 12V as a 32V 10 amp fuse...
Your mileage may vary, of course.
Donald Tsang, proud owner of two Triumph TR7s
tsang@june.cs.washington.edu
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