On 4/30/2008 6:46 PM Tony Hwang spake thus:

Boden wrote:

The purpose of the breaker is to protect the wire from excessive
current. So long as the wire gauge and breaker capacity are matched
properly the size of the load is immaterial.

Hmmm,
Really? wire is link between breaker and the load. Current flowing on
the wire is depending on load. You are trying to say breaker only
protects wires, nothing to do with the load? Does not make sense to me!

The point is that the tripping point of the breaker depends on the
maximum capacity of the wires, *not* the load. Think about it and you'll
see why this is so. I suppose you could say that it's more important to
protect the wires, since they're what can cause fires if overloaded.

So if you have a device that normally draws, let's say, 1 amp on a
20-amp circuit, and the device overloads and draws, let's say, 10 amps,
that device is going to burn up without tripping the breaker. No way to
avoid it, unless the device itself is fused.


--
The best argument against democracy is a five-minute
conversation with the average voter.

- Attributed to Winston Churchill