Re: Ragowski(sp?) coils

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jimlux-at-earthlink-dot-net>

What sort of currents are you trying to measure?  Pulsed discharge, or TC
primary/secondary currents?

For the latter, I'd try something as simple as a current transformer made
with a ferrite toroid with a bunch of windings.  Choose a suitable material
for the toroid to get your frequency response decent.  Calibration might be
a bit of a pain, although a signal generator and load should do nicely.

Your big problems (Rogowski or current transformer) are going to be with
phase shift, etc., coupling from cables, coupling between the UUT and your
probe, etc.

An opto isolated battery powered differential amp measuring the voltage
across a carefully designed shunt might be your best bet.

Or, take a look for hall sensors... MHz frequency responses, in small
packages, with buffer amplifiers, etc.



----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, December 31, 2000 2:27 PM
Subject: Re: Ragowski(sp?) coils


> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
>
> Hi Luc, All,
>
> Thanks a bunch to the several people who responded whith the right
spelling
> and info!  I have about 400 links now to search! :-))  What a difference
> spelling can make when searching for this stuff!!  The integrator thing
> looks nasty and capacitive coupling from high dV/dT (that's us!) are
> problems but I'll see what's what with all this.
>
> Cheers,
>
> Terry
>
>
> At 04:54 PM 12/31/2000 -0500, you wrote:
> >Hi Terry
> >
> >I don't know if it's the same person but a W. Rogowski make work in HV
field,
> >see the Jim Lux web  site.
> >
> >Luc Benard
> >
> >P.S. Happy new year to all of you, I wish you health, peace and serenity
nice
> >coil too ;-))
> >
> >Tesla list wrote:
> >
> >> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
> >>
> >> Hi All,
> >>
> >>         David Mckinnon mentioned using "Ragowski coils" as a possible
high
> >> frequency current tap to measure Tesla coil currents.  I tried
searching
> >> the net for information but I think I am spelling the name "Ragowski"
wrong
> >> and I couldn't find anything.  These are simply air core current
> >> transformers that have high bandwidth.  Perhaps a much better
alternative
> >> to the resistors my fiber probes now use.
> >>
> >> Any info and especially the correct spelling would be appreciated. ;-))
> >>
> >> Cheers,
> >>
> >>         Terry
> >>         terrellf-at-qwest-dot-net
> >
>
>
>