> You'll have to have some faith in the precision of the resistors if you
> have just the basic DMM
>
> I have a meter adapter, based on the AD623, that outputs 1mV/mohm
> using a 4-terminal technique so that wiring, solder joints etc can be
> measured and included/exclude from the required resistance


If the device can handle the current, you can, of course, make your own 4
wire milliohm meter. Just run some known amount of current through the
resistor (using the current limit control on a bench power supply), then
measure the voltage across the resistor at the resistor. I did this on the
1.8V power plane of a PCB where the FPGA was drawing about 6A. I took a
bare board, soldered a wide short across the bypass capacitors at the FPGA
power pins, then drove the power plane and ground plane at the point where
the POLA regulator would go. I then measured the voltage across each
segment of the path (wherever test points were available, such as bypass
capacitors, taps off for other portions of the circuit, etc.). Each
segment then got a calculated milliohm resistance. Various other
calculations could be done from there.

So... you can make your own 4 wire milliohm meter!

Harold


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