Hi Randy. You wrote:
<1) I have equipment which will be tested according to IEC 1010-1. This particular piece of equipment requires a mains 10 amp fuse at 230V line. I looked at some fuse manufacturers and they have fuses rated for what I need, but aren't necessarily IEC approved or are not approved for certain countries (like Denmark only accepts up to 8 amps when using IEC 127 fuses). Are there any fuses which are approved for all countries which can handle the current requirements? I would prefer using the standard 5 mm X 20 mm size fuse. > 20mm fuses are often glass, especially if with 'T' characteristics. This often makes them only suitable for secondary protection, i.e. their interrupt current capacity is often very low, down to 50A or less even. 20mm fuses for use on direct mains connections should be the ceramic tube, sand filled types. In the UK I found some 20mm fuses used on 230V equipment that were only rated at 110V, these fuses were mounted in a filter and simply exploded with some violence when they did blow. With direct mains connections a fuse should really be capable of stopping a prospective short circuit of a few thousand Amps at the supply voltage. 20mm fuses are not ideal, being mainly useful for current limited circuits like transformer secondaries etc. Wherever there is room, I prefer to use 1.25" fuses, ceramic, on mains connections. These turkeys can break 10kA @ 400V. I feel happier with those. In a perfect world you'll use circuit breakers, but you probably don't have room, nobody ever does. Just a tuppence worth... Chris Dupres. Surrey, UK
