On Tuesday, January 1, 2013 8:19:55 PM UTC, wrote:
As part of another project, would like to take some High Current DC measurements.
I have a couple of multimeters ... but obviously not going to be any good for around 80-100A
Now going back to school physics lessons I could use a Shunt resistor ...
http://www.societyofrobots.com/robot...?topic=13900.0
The issue will be obtaining a suitable shunt ... assuming I use a 1 ohm shunt, anybody made one of these ?
The WEB ref page:http://www3.zetatalk.com/docs/Electr...Meter_2007.pdf
details using 12guage copper wire .. based on 1.619 ohm per 1000'
Although maybe a resistance wire may be better eg Nichrome around 10.58" for 1 ohm.
Welcome to any better ideas.


Stable R metals like constantan wire have too much R for this. Low resistance metals like copper change R as they heat up. A simple diy solution when making a shunt from something like copper is to dip it in water, then temp changes are far smaller. In principle you could probably also use a cup-like shape.


NT