>> >...
>>Tom Rauch:
>>>> >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.
>>>>
>>Me:
>>>> ** it is my opinion that the counter-EMF spike can be many times the
>>>> rated primary operating V.
>>>
>>>Yes, Rich, this has always been my understanding also. In fact, it's
>>>difficult to define the extent of the CT primary, to determine the voltage.
>>>The cable may connect from one phase of a power transformer to a bus feeder
>>>breaker 300 ft away. It seems there's always more to things than first meets
>>>the eye. I once listened to a man lecture on "motor stator insulation" for 2
>>>solid days...and he kept my attention! It seemed he lived for motor stators!
>>>A life like that is for people who don't know how to fish.
>>>
>>>Jeff
>>>
>>When DC current abruptly stops, the potential for reverse potential is
>>impressive. I've measured 400v-pk with an o'scope across 24vdc relay
>>coils. I would like to hear Mr. Rauch's explanation of why the operating
>>voltage limits reverse potential.
>>
>>Ever tried fishin' in the amazon? I understand there's a eel-like fish
>>named Electrophorus electricus in there that can do 1kV @ 1A when full
>>grown to c. 6-ft. Presumably, a carbon-fiber fishing rod is not a wise
>>choice
>
> A thousand volts is a bit much, I've read up to 600 or 700 volts,
>depends on the size of the creature.
On a PBS program I heard 1000V for big ones. They had a video of a
crocodile (caiman) who accidently stepped on a big one while he was
wading through some shallows looking for lunch. The croc seemed to come
close to getting toasted or drowned, or both.
>Each of it's electrocytes
>generate .15 volt. Interesting fish huh.
Yes. 6700 puny 0.15v cells in series would not be very puny. Maybe
someday a DXpedition to the Amazon will figure out a way so they won't
have to pack in a generator?
>
have phun, Dale J.
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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