>However my application calls for measuring > 10 amps at
24v which would require a sense resistor of 5 mOhm. How
>on earth (apart from a pcb track which I don't think
>I will be able to measure or make) do I get 5 mOhm ?

This sounds like you are into territory where you start with a piece of
copper bar or tube as the sense resistor, and solder (or more likely bolt) a
couple on wires on it at appropriate tap points.

If you do take this route, then you may need to think about the temp co-eff
of the material used for the bar. If using solid bar, then you can probably
make it in a manner that minimises heat rise due to current flow.

Personally I would start with a piece of copper 1/2" water pipe, work out
from theoretical resistance of copper how far apart the tap points should
be, and solder a couple of wires on and give it a try.

Doing things this way also has the advantage that it is almost impossible to
burn out the current shunt :)

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