Unnamed Administration sources reported that Robert E. Seastrom said:
Bottom line is that one should buy breakers and fuses that are designed for use in DC powerplants, rather than trying to cheap out with something you picked up at Home Depot or Pep Boys. I'm sure I'm wasting my breath since _nobody_ who reads NANOG would ever try to cut corners to save a few bucks... :)
Gawd yes. We all know those little 3AG glass fuses, right? They also come in ceramic. A regular PITA -- you can not look and see they are blown. But they are there for reason. They are typ. full of power to quench the resulting arc. A glass 3AG can and will open, yet the arc just keeps going....slagging the fuseholder, and whatever was errr... protected. There is as much diversity and engineering in fusing as router design. Voltage to be broken, AC vs DC, time curve to open, other factors all enter into it. I see two fuses in series on "pole pigs" primaries around here. Finally had a chance to ask the foreman. One is {say} 10A and that is sized for overloads. The second is 15A, but its sole function is to open FAST if the primary takes a lightning hit and the spark-gap on the transformer conducts. Seems they can't get both qualities right in one fuse so they use two. And RES is correct; DC circuit breakers are different animals than AC by a long shot. Fuses have different ratings as well. RTFM. Please be careful; while you might [now] be easily replaced, the suffering VC's will not appreciate losing all to a dropped tool. ps: I've not even mentioned the acid and H2 gas [kaaBOOM] issues... -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433