fuse values for 100 watt amp

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fuse values for 100 watt amp

Postby nyazzip » Tue Dec 07, 2010 6:56 pm

i am doing a bit of rewiring in a 100 watt(4x el34) guitar amp, which also runs 5 preamp tubes. instead of a fuse, it uses a 7.5 amp circuit breaker, which seems like a heck of a lot of current to draw before a blow....i'd like to replace that with a fuse holder. just wondering what a minimal fuse should be(volts/amps). i will probably always use this amp on half power, too, ie pulling two of the el34s
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Postby EWBrown » Tue Dec 07, 2010 9:39 pm

I'd go with no less than 3 amps and no greater than 5 amps for the fuse, use the "standard" size 250V rated fuses, and avoid using the low voltage (32VDC) rated fuses found at most car parts stores..

Start with a 3A slow-blow, and if it keeps on blowing for no "apparent reason" then use 5A.

/ed B in NC
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Postby Geek » Tue Dec 07, 2010 10:41 pm

I use 4A or 5A (depending on the turn-on surge of the power iron), fast blow for those class of amps and had no callbacks.

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