>> immediately. The CT was probably about 2ft in diameter and 10" thick, with
>a
>> ratio of 1200:5. I was really lucky (blessed) that my knuckle on the same
>> hand was touching ground, as the voltage was tremendous and I don't think
>I
>> would have survived that potential across my chest.
>
>This is a different situation than the flyback or energy storage situation I
>outlined Jeff, because it probably was a sinewave source causing a
>time-varying flux that did not result in an abrupt collapse of field. An
>ignition coil or tank driven by a less-than-class A tube, or an ohmmeter
>across a transformer would have an extra kick (as do relays and motors)
>unless something shorted the backpulse.
>
>In your case the current transformer acts like a normal transformer rather
>than an energy storage system, unless someone broke the line abruptly at a
>sinewave peak. The problem is you can have considerable voltage drop across
>the primary impedance, because the primary impedance can be high if the
>secondary is unterminated. With a sinewave signal you could have had
>hundreds of volts across the primary, which would be stepped up to many
>thousands of secondary volts.
>
>As you learned, an open termination on a current transformer can produce
>some large voltages!! But no more that the turns ratio of the transformer
>and operating voltage would indicate.
** it is my opinion that the counter-EMF spike can be many times the
rated primary operating V.
>A system with an abrupt drop in
>primary excitation, especially if flux density was high, would be a
>different matter.
>
>73 Tom
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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