# How to measure Pulse Current?

Discussion in 'Electronic Equipment' started by GSiu, Jul 9, 2006.

1. ### GSiuGuest

Is there any suggestion how to measure Pulse current up to 10KA and
pulse wide below 10mA?

GSiu, Jul 9, 2006

2. ### Jim YanikGuest

"GSiu" <> wrote in
news::

> Is there any suggestion how to measure Pulse current up to 10KA and
> pulse wide below 10mA?
>
>

below 10ma,a clip-on P6021,P6022(AC)current probe,or a TM500/AM503/A6302
system,DC-50 Mhz BW. The AM503/A6303 probe measures high currents (IIRC,up
to 100's of A),but not 10,000A.

you may need some sort of current transformer for those really high
currents.

--
Jim Yanik
jyanik
at
kua.net

Jim Yanik, Jul 9, 2006

3. ### Robert BaerGuest

Jim Yanik wrote:
> "GSiu" <> wrote in
> news::
>
>
>>Is there any suggestion how to measure Pulse current up to 10KA and
>>pulse wide below 10mA?
>>
>>

>
>
> below 10ma,a clip-on P6021,P6022(AC)current probe,or a TM500/AM503/A6302
> system,DC-50 Mhz BW. The AM503/A6303 probe measures high currents (IIRC,up
> to 100's of A),but not 10,000A.
>
> you may need some sort of current transformer for those really high
> currents.
>

*All* of those probes are current transformers...
At 10,000 amps one would have a problem in preventing saturation; the
secondary winding resistance probably cause enough IR drop that the
current would be low enough so that the current (amps) times turns (=
ampere-turns) would reflect back to the primary (of one turn) so that
the net core flux would be excessive.
Now, it might be done with a *large* core and (relatively) large
diameter wire (to reduce that IR drop)...
So, start with a turns ratio of (say) 10,000 to 1, meaning the
secondary has 10,000 turns.
For insignificant IR drop, the secondary should be no smaller than #20.
From that, figure out the cross-sectional area taken for 10,000
wires, thenmathematically "spread" it out over a torus (if that is the
shape of the core) or rectangle (if "C" or "E" type core).
That should give you a rough idea as to the minimum core size (will
need to be larger due to insulation, etc).

Robert Baer, Jul 9, 2006
4. ### Jim YanikGuest

Robert Baer <> wrote in
news:4r3sg.2197\$:

> Jim Yanik wrote:
>> "GSiu" <> wrote in
>> news::
>>
>>
>>>Is there any suggestion how to measure Pulse current up to 10KA and
>>>pulse wide below 10mA?
>>>
>>>

>>
>>
>> below 10ma,a clip-on P6021,P6022(AC)current probe,or a
>> TM500/AM503/A6302 system,DC-50 Mhz BW. The AM503/A6303 probe measures
>> high currents (IIRC,up to 100's of A),but not 10,000A.
>>
>> you may need some sort of current transformer for those really high
>> currents.
>>

> *All* of those probes are current transformers...

The AM503 probes are Hall-effect devices -with- a current transformer for
hi-freq response.
And they still are PROBES(based on transformers,yes.)
,not a stand-alone transformer.

They also can be slipped over a conductor and not have to be hard-wired
into the circuit.

--
Jim Yanik
jyanik
at
kua.net

Jim Yanik, Jul 9, 2006
5. ### JamieGuest

GSiu wrote:

> Is there any suggestion how to measure Pulse current up to 10KA and
> pulse wide below 10mA?
>

CT..
Current Transformer.
you simply pass the load through
it., the terminals give you a ratio..
something like a 500:1 comes to mind.
also there is the concern of the pulse
width time your looking for ?
also you have Tranducers that can convert
to 4..20, voltage or digitial output etc..

--
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

Jamie, Jul 9, 2006
6. ### Robert BaerGuest

Jim Yanik wrote:

> Robert Baer <> wrote in
> news:4r3sg.2197\$:
>
>
>>Jim Yanik wrote:
>>
>>>"GSiu" <> wrote in
>>>news::
>>>
>>>
>>>
>>>>Is there any suggestion how to measure Pulse current up to 10KA and
>>>>pulse wide below 10mA?
>>>>
>>>>
>>>
>>>
>>>below 10ma,a clip-on P6021,P6022(AC)current probe,or a
>>>TM500/AM503/A6302 system,DC-50 Mhz BW. The AM503/A6303 probe measures
>>>high currents (IIRC,up to 100's of A),but not 10,000A.
>>>
>>>you may need some sort of current transformer for those really high
>>>currents.
>>>

>>
>> *All* of those probes are current transformers...

>
>
> The AM503 probes are Hall-effect devices -with- a current transformer for
> hi-freq response.
> And they still are PROBES(based on transformers,yes.)
> ,not a stand-alone transformer.
>
> They also can be slipped over a conductor and not have to be hard-wired
> into the circuit.
>

I believe this is the first time that "stand-alone" was mentioned...

Robert Baer, Jul 10, 2006
7. ### John McMillanGuest

In article <UYhsg.6490\$>,
Robert Baer <> wrote:

> Jim Yanik wrote:
>
> > Robert Baer <> wrote in
> > news:4r3sg.2197\$:
> >
> >
> >>Jim Yanik wrote:
> >>
> >>>"GSiu" <> wrote in
> >>>news::
> >>>
> >>>
> >>>
> >>>>Is there any suggestion how to measure Pulse current up to 10KA and
> >>>>pulse wide below 10mA?

Rogowski coil?

John McMillan, Jul 10, 2006
8. ### Robert BaerGuest

John McMillan wrote:

> In article <UYhsg.6490\$>,
> Robert Baer <> wrote:
>
>
>>Jim Yanik wrote:
>>
>>
>>>Robert Baer <> wrote in
>>>news:4r3sg.2197\$:
>>>
>>>
>>>
>>>>Jim Yanik wrote:
>>>>
>>>>
>>>>>"GSiu" <> wrote in
>>>>>news::
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>Is there any suggestion how to measure Pulse current up to 10KA and
>>>>>>pulse wide below 10mA?

>
>
> Rogowski coil?

Wow! Used Google to find out what that was, and the first hit, the
PDF is very illuminating and useful.

Robert Baer, Jul 10, 2006
9. ### John McMillanGuest

In article <yczsg.5621\$>,
Robert Baer <> wrote:

> John McMillan wrote:
>

> >>>>>>Is there any suggestion how to measure Pulse current up to 10KA and
> >>>>>>pulse wide below 10mA?

> >
> >
> > Rogowski coil?

> Wow! Used Google to find out what that was, and the first hit, the
> PDF is very illuminating and useful.

I had a summer job at Culham lab years back and we used to make
these things out of stripped Hackethal delay cable. I don't
suppose you can still get Hackethal or anything like it.
Last year I built myself a tiny Rogowski coil by soldering eight surface
mount inductors into an octagon. It worked too!

John McMillan, Jul 14, 2006