Hi, Carlos, On Monday 21 March 2005 12:40, Carlos E. R. wrote:
The Monday 2005-03-21 at 06:56 -0800, Randall R Schulz wrote:
GFCIs essentially _infer_ that current is traveling to ground because there's unequal current flow through the two power wires. (Kirchoff's laws to the rescue). The _assumption_ (a conservative one) is that the current is flowing through a human. Humans are notoriously ill-suited for use as electrical conductors.
English is a nice language for some kind of humor :-p
Hmmm... I wonder, how do GFCIs deal with reactive loads? Do they time average the current measurement over several cycles?
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Thus, they are current sensitive devices. They don't sense voltage, only instantaneous current (really average), and thus know nothing about reactive load (ie, they can not measure the I·A phase difference), they are all the same to it. They would trigger.
Right, right. That's why I switched from EE to CS. Del dot B = 0 my ass. Electrostatics was tolerable, but electrodynamics was just not worth it. And what's the deal with exponentials in the current / voltage relationship in semiconductor junctions? That's nuts!
Carlos Robinson
Randall Schulz