how to measure surface resistivity using 4 point probe methord?
anyone?

 

Attach two probes near outer surface of material under test.. Apply a source voltage to these. Between these two probes, attach the sensor probes. Measure the voltage differential betwen the two sensor probes.

You need to know the surface area, and the spacing between the probes. I've got the actual formula somewhere. Stand by.!

Eric

 

I vaguely recall that you force a current between the outer probes, and measure the voltage between the inner probes. The geometry factors out as long as the probes are colinear and equally spaced.

 

Visit Biddle's application page ... http://www.biddlemegger.com/cgi-bin/webshop.cgi?config=ent-apps

The manual, Getting down to earth, talks about ground resistivity.