Re: Breaker panel current transformer?

Anno Siegel wrote: 
 <pjk@xxxxxxxxxxxxxx> wrote in sci.electronics.design:

On Mon, 23 May 2005 02:03:59 GMT, Ross Herbert
<rherber1@xxxxxxxxxxxxxx> wrote:

On 21 May 2005 09:10:48 -0700, "BobG" <bobgardner@xxxxxxx> wrote: 


[...]


voltage.I would expect the most likely circumstance to produce
dangerous voltages on the output of a current transformer is a short
circuit on the load being monitored.

Contrary to Richard Grise's comment, when the secondary impedance is
high the output voltage will still be limited by the voltage drop
across the primary inductance time the turns ratio. ...


If the load is a short, you *will* have full voltage across the primary.

Not quite. You will have most of the full line voltage dropped across the entire wiring loop after the last distribution transformer, including its secondary resistance, and its leakage inductance. A little of the voltage will drop on the high voltage side of that transformer. Only a small fraction of that total drop will occur across the inductance of the current transformer, and then, only till the core saturates each half cycle (and there won't be many of those till something pops).
.

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