[samplesj]

I'm going to switch out my amp's transformer to a 1000va unit.  At the same time I'll be installing a hypex softstart board since this would pop breakers or eat fuses without it.

I saw a few places on the web it was a good idea to fuse at 125% of the rated capacity.  So should the proper size fuse be 5A/250V (= 10A/120V = 1200VA pretty close to 125%)?  Because of the softstart I don't need to way oversize it right?  I should also point out that I think the two UCD400s I'm feeding max somewhere just above 800VA draw.  

I guess I could try this and if it pops put in a bigger one, but I'd have to make another trip to town .

I'm guessing this should be a slow blow, but I don't know for sure so I wanted to double check that too.

[larry99]

Just select for the amp rating. The voltage rating is for the voltage that the fuse will block after it burns open. The 125% rule applied to current is probably OK. You want the fuse current rating to be as low as possible to prevent damage to other components or prevent a fire. It's better to be too low and have to step up the current rating than to be too high and have bigger problems than a blown fuse.

[peranders]

1000 VA

230 VAC => 3.15 AT or 4 or 5 A fast

Double the rating for 110/120 VAC