Reply to post: Re: anything from 1A to 13A

Sysadmin unplugged wrong server, ran away, hoped nobody noticed

albegadeep

Re: anything from 1A to 13A

"The logical solution is a "bus" architecture"

I think we're talking about pretty much the same thing, but maybe I wasn't clear on my original statement. Here's an example of what I mean: My garage has 14 outlets, each designed for 120V 20A. I'm likely to pull some serious current in total (electric heater, air compressor, and lathe all at once, for instance), so it's split in 4 circuits, each with its own 20A breaker. 2-conductor (plus ground) wiring rated for 20A starts at the breaker, goes to the first outlet, from there to the second, and so on, stopping at the last outlet on the circuit - "radial" as opposed to ring. Pull over 20A on any one outlet, and a breaker trips, but there's 80A available in total.

Most equipment (house or garage) has a built-in, hard-wired cable rated higher than what the equipment should ever pull - but no fuse. Lamps, radios, and other low-power devices often have smaller cables; I can see why a fuse would be a good idea, in this case.

In contrast, most computer equipment has a cable that is removable at both ends. These are typically larger than those for lamps and radios, but are a fairly standard cable size and (presumably) rating - any "computer cable" can be used in any application, because the protection is provided by the breaker, and the outlet and in-wall wiring can take the breaker's trip current. If the equipment itself needs protecting, the manufacturer builds in a fuse to the equipment, not the cable.

(Side note: most house outlets are 15A; 20A outlets have a slightly different pin configuration. 20A outlets will accept 15A plugs, but not the other way around.)

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