Measure resistance with NI USB-6363 ... need constant current source?

[josborne]

Hi,

Can some advise how to measure resistance with my NI USB-6363?

I want to measure a low resistance (<100 ohm), so I'd like to use the 4-wire technique as described here:

http://zone.ni.com/reference/en-XX/help/370466AC-01/measfunds/4wireres/

Can I do this with a NI USB-6363?  According to the link above, it looks like I need a constant current source (Iex)? 

Thanks for your tips.

[Oligarlicky]

How accurate do you need to be. You don't actually need a constant current source (though, that is the preferred method), you can get by with using a sense resistor. You measure the current, you measure the voltage, and you have the resistance. It won't be fantastically accurate (probably limited by your sense resistor) but it'll do the job.

[AnalogKid2DigitalMan]

If you need a constant current source, Google 'LM317 constant current source'.

Only the regulator and a resistor are needed to construct one, I often use that scheme to power high intensity LED's.

-AK2DM